The Integrated Design Process

Preparation for the project can be led by many players but generally comes from the user/client who identifies the need for building on the basis of quantifiable requirements for space and budgetary capacity to undertake the activity. A needs assessment often accompanies this planning activity—it can describe existing space use; develop realistic estimates of requirements, both spatial and technical; and arrive at a space program around which design activity can develop. For larger projects, a construction manager or a general contractor may be engaged at this point. See also WBDG Project Management and Programming.

Once the Pre-design activities are complete, the architect or other prime consultant, in consultation with his or her team of sub-consultants, may produce initial graphic suggestions for the project or portions of it. Such suggestions are meant to stimulate thought and discussion, not necessarily to describe the final outcome. Involvement of sub-consultants is a critical part of the process at this stage - their individual insights made at this point can prevent costly changes further along in the process. Gradually a design emerges which embodies the interests and requirements of all participants while also meeting the overall area requirements which the project budget will have established during Pre-Design activities. The resulting Schematic Designs produced at this stage show site location and organization, general building shape, space allocation, and an outline specification which makes an initial list of components and systems to be designed and/or specified for the final result. Depending on the size of the project, it is often useful to have a cost estimate performed by a professional cost estimator at this point. For smaller projects, one or more possible builders may perform this service as part of a preliminary bidding arrangement—selection can be made on the basis of an estimate at this stage. On larger projects, a cost estimate can be part of the selection process for a builder, assuming other prerequisites like bonding capacity, experience with the type, and satisfactory references are met.

Design Development enlarges the scale of consideration—greater detail is developed for all aspects of the building—the collaborative process continues with the architect providing graphic focus for the various contributors. Greater detail is considered for all aspects of the building. The conclusion of this phase is a detailed design on which all players agree and may be asked to sign off.

The Development of Contract Documents involves translating the Design Development information into formats suitable for pricing, permitting, and construction. No set of contract documents can ever be perfect, but high quality can be achieved by scrutiny, accountability to the initial program needs by the design team and the client, along with careful coordination among the technical consultants on the design team. Decisions continue to be made with the appropriate contributions of all players. Changes in scopes during this phase will become more expensive once pricing has begun. Changes to the contract documents invite confusion, errors, and added costs. Cost estimates by an estimator may be made at this point, prior to or simultaneous with bidding, in order to assure compliance with the budget and to check the bids. Bids taken at this point may be used as a basis for selecting a builder.

After the general contractor is selected and during the Construction Phase, the designers and other members of the team must remain fully involved. Decisions previously made may require clarification; suppliers' information must be reviewed for compliance with the Contract Documents; and substitutions must be evaluated. Contract Documents are never perfect—clarifications will be required. If changes affect the operation of the building, it is especially important that the user/client be involved. User requirements may change, necessitating changes in the building—these changes

require broad consultation among the consultants and sub-consultants, pricing, and incorporation into the contract documents and the building.

The design team is responsible for assuring that the building meets the requirements of the Contract Documents, but the building's success at meeting the requirements of the original program can be assessed by the construction management team or third parties in a process known as Commissioning. Here the full range of functions in the building is evaluated and the design and construction team can be called upon to make changes and adjustments as needed.

After the building is fully operational, it is often useful to conduct a Post-Occupancy Evaluation to assess how the building meets the original and emerging requirements for its use. Such information is especially useful when further construction of the same type is contemplated by the same user. Mistakes can be prevented and successes repeated.

This summary describes the standard operation of the integrated project team. Such a model is neither new nor exceptional. But it depends on:

1. clear and continuous communication 2. rigorous attention to detail 3. active collaboration among all team members

—adherence to these principles will assure the best result.

Engage the Integrated Design Processby the WBDG Aesthetics Subcommittee

Design Objectives Index > Aesthetics

> - Engage the Appropriate Language and Elements of Design

- Engage the Integrated Design Process- Select Appropriate Design Professionals- Design Awards

OVERVIEW

The design of buildings requires the integration of many kinds of information into a synthetic whole. An integrated process, or "whole building" design process, includes the active and continuing participation of users, code officials, building technologists, cost consultants, civil engineers, mechanical and electrical engineers, structural engineers, specifications specialists, and consultants from many specialized fields. The best buildings result from active, consistent, organized collaboration among all players. (See the Design Disciplines branch of the WBDG to learn more about the role of design disciplines in the whole building process.)

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The integrated design process enables project team members to work together from the project outset to develop solutions that have multiple benefits.

A. The Integrated Design Process

Preparation for the project can be led by many players but generally comes from the user/client who identifies the need for building on the basis of quantifiable requirements for space and budgetary capacity to undertake the activity. A needs assessment often accompanies this planning activity—it can describe existing space use; develop realistic estimates of requirements, both spatial and technical; and arrive at a space program around which design activity can develop. For larger projects, a construction manager or a general contractor may be engaged at this point. See also WBDG Project Management and Programming.

Once the Pre-design activities are complete, the architect or other prime consultant, in consultation with his or her team of sub-consultants, may produce initial graphic suggestions for the project or portions of it. Such suggestions are meant to stimulate thought and discussion, not necessarily to describe the final outcome. Involvement of sub-consultants is a critical part of the process at this stage - their individual insights made at this point can prevent costly changes further along in the process. Gradually a design emerges which embodies the interests and requirements of all participants while also meeting the overall area requirements which the project budget will have established during Pre-Design activities. The resulting Schematic Designs produced at this stage show site location and organization, general building shape, space allocation, and an outline specification which makes an initial list of components and systems to be designed and/or specified for the final result. Depending on the size of the project, it is often useful to have a cost estimate performed by a professional cost estimator at this point. For smaller projects, one or more possible builders may perform this service as part of a preliminary bidding arrangement—selection can be made on the basis of an estimate at this stage. On larger projects, a cost estimate can be part of the selection process for a builder, assuming other prerequisites like bonding capacity, experience with the type, and satisfactory references are met.

Design Development enlarges the scale of consideration—greater detail is developed for all aspects of the building—the collaborative process continues with the architect providing graphic focus for the various contributors. Greater detail is considered for all aspects of the building. The conclusion of this phase is a detailed design on which all players agree and may be asked to sign off.

The Development of Contract Documents involves translating the Design Development information into formats suitable for pricing, permitting, and construction. No set of contract documents can ever be perfect, but high quality can be achieved by scrutiny, accountability to the initial program needs by the design team and the client, along with careful coordination among the technical consultants on the design team. Decisions continue to be made with the appropriate contributions of all players. Changes in scopes during this phase will become more expensive once

pricing has begun. Changes to the contract documents invite confusion, errors, and added costs. Cost estimates by an estimator may be made at this point, prior to or simultaneous with bidding, in order to assure compliance with the budget and to check the bids. Bids taken at this point may be used as a basis for selecting a builder.

After the general contractor is selected and during the Construction Phase, the designers and other members of the team must remain fully involved. Decisions previously made may require clarification; suppliers' information must be reviewed for compliance with the Contract Documents; and substitutions must be evaluated. Contract Documents are never perfect—clarifications will be required. If changes affect the operation of the building, it is especially important that the user/client be involved. User requirements may change, necessitating changes in the building—these changes require broad consultation among the consultants and sub-consultants, pricing, and incorporation into the contract documents and the building.

The design team is responsible for assuring that the building meets the requirements of the Contract Documents, but the building's success at meeting the requirements of the original program can be assessed by the construction management team or third parties in a process known as Commissioning. Here the full range of functions in the building is evaluated and the design and construction team can be called upon to make changes and adjustments as needed.

After the building is fully operational, it is often useful to conduct a Post-Occupancy Evaluation to assess how the building meets the original and emerging requirements for its use. Such information is especially useful when further construction of the same type is contemplated by the same user. Mistakes can be prevented and successes repeated.

This summary describes the standard operation of the integrated project team. Such a model is neither new nor exceptional. But it depends on:

1. clear and continuous communication 2. rigorous attention to detail 3. active collaboration among all team members

—adherence to these principles will assure the best result.

B. The Integrated, Multidisciplinary Project Team

Team Members in a process like this may include the following:

The Owner's Representative: this person must speak for the owner and be prepared to devote the time needed to fully advocate, defend, clarify, and develop the owner's interests. This person may come from within the organization commissioning the project or may be hired as a consultant.

The Construction Manager: this professional is hired on a fee basis to represent the logistics and costs of the construction process. This person can be an architect, a general contractor, or specifically a consulting Construction Manager. It is beneficial for this person to be involved from the beginning of the project.

The Architect acts as the lead designer in most building projects, coordinating the sub-consultants, assuring compliance with the program, and assuring compliance with the budget. In some cases, the architect hires some or all of the sub-consultants; in larger projects the owner may contract directly with some or all of them. He or she provides the progressively more precise and detailed suggestions for the form of the result and manages the production of the contract documents. The architect usually participates in the construction phase of the project, assessing compliance with the contract documents by managing appropriate inspections, submissions approvals, and evaluations by the sub-consultants. The architect assists in the evaluation of requests for payment by the builder.

The Civil Engineer is essential for understanding the land, soil, and regulatory aspects of any construction project; early involvement is essential and the civil engineer is frequently hired directly by the owner in advance of the rest of the design team. The civil engineer prepares his or her own contract documents and assesses compliance of the work with the contract documents.

The Landscape Architect is often part of the civil engineer's resources, but can also be involved as an independent consultant. In either case, the landscape architect should be involved early in the project to assess natural systems, how they will be affected by the project and the best ways to accommodate the project to those systems.

Consulting Structural, Mechanical, and Electrical Engineers can be engaged by the architect as part of his work or, on larger or more complex projects, may be engaged separately by the owner. They are responsible for the structural, heating, ventilating and air-conditioning and the power, signal, and illumination aspects of the project. Each produces his or her own portions of the contract documents and should be involved in assessing their part of the work for compliance with those documents.

Specialized Consultants should be involved as needed by the special requirements of the project. These may include specifications writers, materials and component specialists, sustainability consultants, and technical specialists like kitchen, audio-visual, materials handling, and parking. The size, complexity, and specialization of the project will suggest the kinds of additional experts who will be needed. Like all contributors to the integrated design process, they should be involved early enough to include their suggestions and requirements in the design, not so late that their contributions must be remedial.

C. Results

The best buildings in history are the result of high degrees of consistency at all levels

of their realization. The simplicity in massing of the Seagram Building by Mies van der Rohe in New York City, for example, is supported by the building's subtle and spare details at every level. Design attention is applied to the massing and the drinking fountains, the site plan, and the door details. Good buildings result from an appreciation by all involved of the importance of formal consistency throughout the design.

Start Right – Set energy goal and assemble design teamPre-Design – Investigate energy design conceptsSchematic Design – Simulate and compare energy strategiesDesign Development – Confirm that your design energy meets the targetConstruction & Bid Documents – Include energy goal in specsFollow Through – Commission building, rate operational performance,and apply for ENERGY STAR

Start Right: Set Goal - Assemble Design Team

Setting a definitive and measurable energy performance target is an important step in designing sustainable buildings that reduce operating costs and prevent pollution. Once your goal is set, a method to achieve it is required.

Action Items

← Set an energy performance target by using the EPA Energy Performance Rating — Target Finder — for design projects.

← Use energy design guidance to help choose energy-efficient strategies and technologies that will achieve your target. See Advanced Building Guidelines — E-Benchmark — at Building Design Links.

← Review case studies that demonstrate enhanced energy performance in buildings similar to your project. See Resources for case studies and links to profiles of ENERGY STAR labeled buildings.

← Review your firm's relevant past projects and compare their energy performance with the target for your new project. Consider touring local facilities to understand how design and energy strategies were successfully implemented.

← Consider financial and environmental impacts by using Target Finder to assess the cost of target energy use and the associated greenhouse gas emissions for the design.

← Work with client to allocate sufficient funds to carry out an integrated design process and reach your energy performance target.

Assemble Design Team

Achieving superior energy performance requires assembling a multi-disciplinary team that works together from goal setting to building operation. The team should investigate energy performance design strategies and determine how these strategies can be integrated in the design. Team buy-in, experience, and early involvement are vital so that they can establish and achieve design and energy performance goals.

Action Items

← Select a multi-disciplinary team early in the process, including the building owner, architects, energy consultants, engineers, proposed tenants, state and local government officials, construction contractors, commissioning agent, and Operations & Maintenance (O&M) staff.

← Adopt an integrated design approach and educate the project team on goals, costs, and benefits of the process. Use a front-loaded, research-intensive process to determine strategies for creating buildings that achieve energy performance goals.

Pre-Design

The conventional design process usually introduces energy-efficient technologies during design development. However, the greatest opportunity for cost-effective energy measures occurs earlier in the design process. The pre-design stage is when the team investigates energy-related design concepts that consider the environment, climate, building orientation, and other features that will impact performance well into the future.

Action Items

← Have a facilitated charrette that includes addressing energy objectives pertinent to the design. Identify synergies between design concepts and energy use. Develop a plan and adopt a method for delivering a top performing energy-efficient building. Determine requirements needed to start schematic design.

← Develop scope of work, project budget, and schedule, which include energy-efficient strategies and your performance target.

Schematic Design

As the team's ideas are taking form during schematic design, do preliminary simulations of various energy options and technologies. Compare the results to your energy target to know which strategies meet your goal.

Action Items

← Analyze the site based on how it will affect energy and determine building orientation that enhances energy performance. Use natural shading features to reduce cooling load. Consider daylighting to reduce electrical lighting requirement and the air-conditioning load. These contribute to quality of the space.

← Use energy design guidance to select the technologies that help deliver superior energy performance and indoor environmental quality. Right-size mechanical systems based on anticipated systems performance and loads, rather than rules of thumb. Ensure compliance with energy codes and standards during schematic design rather than tweaking

the design later in the process. Enhance code compliance by using the Advanced Building Guidelines — E-Benchmark — at Building Design Links.

← Include energy expert to review the selected energy strategies and provide preliminary costs and benefits for various design options. Begin energy analysis of design concepts using appropriate system design tools. Perform progressive analysis during schematic design to determine the relative efficiency of energy strategies and make improvements to your design.

← Compare estimated energy use to design target using Target Finder. Make adjustments and integrate energy performance strategies in building design to achieve your performance target.

Design Development

Refine the project in Design Development and confirm that your energy performance target can be achieved. Include the energy performance goal in specification language.

Action Items

← Prepare energy performance specification with estimated energy use target, anticipated outcome, and compliance schedule. Include the Building Energy Performance

Specification in construction documents. ← Identify energy-efficient design elements that require careful specification and

assemble resources that explain installation, operation, and any other requirements. ← Gather manufacturers' technical literature for energy systems and components to

include in construction documents and for use during building commissioning. Supplement literature with design team's summaries of intended operation.

Construction & Bid Documents

It is important to select a qualified construction team that is able to execute the specified energy efficiency strategies that meet your design target. Seek a contractor who has a track record for constructing buildings that achieve superior energy performance.

Action Items

← Include Statement of Energy Design Intent (SEDI) from Target Finder, which shows the intended energy performance outcome for your design in final construction documents and bid package.

← Specify design team participation during construction to ensure that energy performance features are incorporated and to help produce a more comprehensive set of as-built documents.

← Include approval process for change orders to methods and materials prior to construction, or require design team supervision during construction. Encourage building owner or designee to hold all parties accountable for achieving your energy performance goal.

← Document construction methods associated with specific energy-efficient products and materials by including manufacturers' literature and contact information for local technical reps. Include design team's summaries of energy-efficient features in specifications and drawings. Explain anticipated functions of features to assist construction team in understanding desired outcome.

← Select qualified manufacturers and do not accept unapproved alternatives for installing/constructing key energy-efficient features/systems. Be specific with explanations to all manufacturers so that proposals are compatible with one another.

← Seek incentives for meeting your energy performance goal. Local utility companies may offer incentives to offset costs for the design team/owner to explore options that achieve the desired energy performance target.

← Communicate your superior energy design intent by placing the "Designed To Earn The ENERGY STAR" graphic on final drawings that achieve 75 or better in Target Finder.

Commissioning is the process of verifying that a new building functions as intended and communicating the intended performance to the building management team. This usually occurs when the building is turned over for occupancy. In practice, commissioning costs aren't included in design fees and often compete with other activities. As a result, it is seldom pursued properly. It is critical that the building is commissioned to ensure that energy performance and operational goals are met.

Action Items

← Communicate your energy performance goal during commissioning to ensure that the design target is met. Encourage energy-use tracking that will allow performance comparisons to be made over time.

← Specify detailed commissioning activities in your project contracts. Seek separate funding for commissioning work to ensure that it is given the appropriate level of importance.

← Hire experts that specialize in building commissioning. Include the commissioning firm as part of the design team early in the project.

← Finalize and transfer a set technical documents including manufacturers' literature for systems and components. Supplement technical literature with summaries of intended operation. Provide additional explanation for innovative design features.

Tracking, Measurement & Verification

Building automation systems in commercial buildings allow users to track actual energy consumption over time. In contrast, the EPA Energy Performance Rating allows users to evaluate overall annual building performance using a 1-100 scale.

Action Items

← Communicate the energy performance target (of your design) to the M&V team and ensure they understand specific performance expectations for the new building.

← Document how sustained energy performance compares to the design intent and best practices from the project design.

← Use EPA's Web-based Portfolio Manager, once the building has been operating for 12 months, to track and rate annual energy performance. To check a building's eligibility for ENERGY STAR, see "Evaluate Building Performance" on the ENERGY STAR Web site.

The selection of the design team should be undertaken as early in the life of a project as possible. Every design and construction project is unique, with a variety of services required to transform the generalized concept into reality. A qualified design professional can guide an owner through the intricacies of the design process; standard phases include pre-design, concept design, design development, construction documentation, bidding and negotiations, and construction. Building design professionals can assist in defining the project at the outset in terms that provide meaningful guidance for design. Pre-design services might include site selection, existing facilities surveys, environmental studies and reports, feasibility and programming studies. Design services, in addition to the standards phases of design, might include Building Information Modeling, LEED certification, and commissioning. It is important to begin the process of selecting design professionals with a consideration of

delivery method, and site, programmatic, schedule, and budget issues. These factors contribute to defining the scope of work for projects, which in turn inform the selection of appropriate design professionals and delivery team composition.

A. Selecting Design Professionals

When a building project is initiated by an agency representing the public, the selection of a qualified building professional becomes a reflection of how tax dollars will be spent. When selecting a design professional, a public owner's primary concerns are to get the best available design services and outcome, and to conduct a fair and equitable selection process. Once that selection has been made, it is then the responsibility of the agency to negotiate the best value for those services; but first, the selection panel should ensure the selection of the best available firm for the project. A building project is a long-term investment, and the realized, built project will be a testament to how well thought-out the selection process is.

For public projects, there are two main methods for selecting design professionals: Qualifications-Based Selection and Design Competitions. In either method, the individuals responsible for selecting the design professional should have an understanding of the needs of a specific project and should be able to evaluate the achievements of the potential firms. Selection panels evaluate firms on criteria such as previous experience, past performance, portfolio review, awards and recognitions, level of commitment to project, and overall customer service.

To ensure the selection panel will make a well informed choice, it is important that any procurement for professional design services take into consideration:

The goals of the project. Solicitations for qualifications and requests for proposals should be specific about the goals and parameters of the project, the anticipated scope of work, and any specialty disciplines that will be required. Be clear about what will be expected of the design team and what evaluation factors will be used to select them.

The design team's suitability for the project. This does not mean an AE must have done the same type of project, but that his/her experience demonstrates a competency in projects of similar complexity or context.

Who is in charge. Complex needs may be addressed by a complex team; make sure you know who is in charge and how the team is structured.

Qualifications-Based Selection (QBS)

Qualifications-Based Selection - When a building project is initiated by an agency representing the public, the selection of a qualified building professional becomes even more important. When selecting a design professional, a public owner's primary concerns are to get the best available design services, and conduct a fair and equitable selection process. Federal project solicitations are announced in FedBizOpps.gov, a website that lists government-wide notices for all types of services.

Recognizing the need for a qualifications-based approach to procuring design services, the U.S. Congress established as federal law in 1972 (P.L. 92-582), commonly referred to as the "Brooks Act", that requires that architects and engineers be selected for projects on the basis of their qualifications subject to negotiation of fair and reasonable compensation. Selection panel members must be highly qualified professionals with experience in design and construction related fields. Most states and numerous local jurisdictions also use Brooks Act procedures.

Qualifications-Based Selection (QBS) usually involve the following steps:

1. The owner prepares a description of the project to be built or problem to be solved, referred to as a preliminary scope of services.

2. The owner invites design professionals to submit statements of qualifications for the project at hand.

3. Statements of qualifications are evaluated and several individuals or firms are selected, or "short-listed," for further consideration.

4. The individuals or firms are then interviewed and ranked according to an evaluative scoring system.

Design Competitions

A design competition is a method of awarding a design contract based on design excellence and is a permitted selection method allowed by FAR 36.602-1b. When the use of a design competition is approved by the agency head or designee, the agency may evaluate firms based on their conceptual design of a project. Design competitions are typically used for significant Federal projects, such as monuments or those of unusual national significance. Since selection of the design firm takes longer when a competition is used as the selection method, there must be sufficient time in the project schedule to produce and evaluate conceptual designs. There must also be a significant benefit to the project to use a competition as this selection vehicle also costs more.

There are two types of federal design competitions: Open design competitions are open to all design professionals. These are usually

design teams headed by an architectural firm with a registered architect at the helm. An example of this is the World War II Memorial Competition, won by Freidrich St. Florian.

Invited design competitions are competitions where a selected group of design professionals, usually highly regarded or recognized architects, are invited to submit a design on a project. This is often the last stage of a qualifications-based selection process. An example of this is the proposed Federal Courthouse in Rockford, IL, won by Koetter Kim Architects.

Competitions are structured as a one-stage, two-stage, or in some cases, a three-stage process:

In a One-Stage design competition, the selected firm is chosen by a jury from all submitted entries. The winner is then awarded the design contract. Because of the nature of projects that lend themselves to Federal Design Competitions, this type of competition is not used very often.

A Two-Stage design competition is also open to all design professionals. The goal of the first stage is to solicit design portfolios from Design Firms and Lead Designers. Based on the jury evaluation of the submitted portfolios, a short-list of Design Firms and Lead Designers is selected to proceed to Stage II. The highest ranking competitors are then invited to form complete A/E teams, and submit additional written material on the teams for further evaluation by the agency's A/E Evaluation Board. During Stage II, team interviews are also held. A final ranking of the teams is completed by the A/E Evaluation Board, who then makes the final selection.

A Three-Stage competition incorporates the same components as the One- and Two-Stage competition, however final selection is made following completion of a "vision" for the project. The evaluation of the design concepts by an independent jury, as well as the evaluations of the Stage I and Stage II components, will be used by the A/E Evaluation Board to prepare the final ranking of the Stage III Teams. Because of the additional expense associated with preparing project "vision" submittals, teams are compensated with an amount that is specified in the original announcement in FedBizOpps.gov.

Project Requirements

Project inception and preliminary planning require thoughtful definition of goals and needs (Project Scope); master planning to accommodate anticipated future needs; evaluation of project alternatives; identification of site requirements; funding requirements; budget authorization cycles and/or financial impacts; and project phasing.

Delivery Methods

There are many approaches to achieve successful project design and construction. These "Delivery Methods", which are driven by the project's scope, budget, and schedule, include Traditional (Design/Bid/Build), CM (also called CMc, or Construction Manager as Constructor), Design-Build, Bridging, and Lease/Build. The selection of a delivery method will in turn influence the Delivery Team composition, schedule, budget, and management plan.

Project Management Plans

A Project Management Plan (PMP) is commonly used to document key management parameters in a central location and is updated throughout the project focusing on recognition of changes in program planning and management of those changes. It includes definition of an owner's program goals, technical requirements, schedules, resources, budgets, and management programs.

Design Stage Management

Once a design team has been assembled (procured), a high level of owner coordination is needed to manage the entire delivery team through the project's design phases. Design management requires oversight of schedules and budgets; review of key submissions and deliverables for compliance with program goals and design objectives; verification of incorporation of stakeholder review input; verification of incorporation of construction phase functional testing requirements; and appropriate application of the owner's design standards and criteria.

Construction Stage Management

Project coordination/communication RFIs Change order management Conflict resolution

Inspections Submittal reviews Schedules Payments

Building Commissioning

Commissioning (Cx) is a systematic process of ensuring that building systems perform interactively according to the design intent and the owner's operational needs. This is achieved by documenting the owner's requirements and assuring those requirements are met throughout the entire delivery process. This involves actual verification of

systems performance and integration; comprehensive operation and maintenance (O&M) documentation; and training of the operating personnel. Building Commissioning procedures may include: Commissioning Plans, Total Building Commissioning, Systems Commissioning, Pre-installation Performance Testing/Commissioning, Re-Commissioning, Retro-Commissioning, and LEED Certification.

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INTRODUCTION

Accurately forecasting the cost of future projects is vital to the survival of any business or organization contemplating future construction. Cost estimators develop the cost information that business owners or managers, professional design team members, and construction contractors need to make budgetary and feasibility determinations. From an Owner's perspective the cost estimate may be used to determine the project scope or whether the project should proceed. The construction contractor's cost estimate will determine the construction bid or whether the company will bid on the construction contract.

There were about 198,000 cost estimators in 1994 according to the U.S. Department of Labor, Bureau of Labor Statistics, 2006-2007 Occupational Outlook Handbook, Cost Estimators, of which 58% work in the construction industry, 17% are employed in manufacturing industries, and the remaining 25% elsewhere. Most construction estimators have considerable experience gained through working in the building construction industry. This guide will be confined to cost estimating in the building construction industry.

Construction cost estimators can be contractually hired in many different ways. They may be employed by the owner's representative/project manager, employed by the construction manager, employed as a member of a professional design team, or separately hired by the owner. They estimate building costs through all the stages of design and the construction of the project. On large projects it is common for estimators to specialize in disciplines that parallel design discipline specialization.

It is very important to have the cost estimator involved right from the start of the project to ensure that the project budget reflects the decisions made by the rest of the project team throughout the integrated design process.

DESCRIPTION

A. Professional Behavior Expected of the Cost Estimator

Ethics: The practice of construction estimating is a highly technical and professional discipline. It also involves abiding by certain standards of ethical conduct and moral judgment that go beyond the technical aspects of the discipline. Estimators are often the most familiar with the complete project. They must exercise sound moral and professional judgment at all times when preparing the project estimate. Estimators sometime receive pressure from other members of the construction team to make expedient short-term decisions that can result in an unsound bid. Resistance to this type of pressure is a part of the estimator's job. Examples of expedient behavior litter the history of

inaccurate construction estimating. Deficient estimates can also cause strife and litigation between members of the construction team. The American Society of Professional Estimators (ASPE) has stated the following ethical, moral and technical precepts as basic to the practice of estimating. See the ASPE, Canon of Ethics.

Integrity: Estimators are expected to use standards of confidentiality in a manner at least equal to that of other professional societies. The estimator shall keep in strictest confidence information received from outside sources. The practice, commonly called "bid peddling", is a breach of ethics and is condemned by the ASPE and that of other societies and construction organizations.

Judgment: Judgment is a skill obtained by estimators through proper training and extensive experience. Estimators should always use sound judgment and common sense when preparing estimates. Proper use of judgment may mean the difference between profit and loss for the company or client.

Attitude: Estimators should approach each estimate with a professional attitude and examine in thorough detail all areas of the work. They will set aside specific times each day for entry of estimate quantities and data without interruption. Total mental concentration is a basic requirement for preparing accurate cost estimates.

Thoroughness: An estimator will allow enough time to research and become familiar with the background and details of the project and then promptly complete the quantity survey. They will review the various aspects of the project with the other disciplines involved. The estimator with the most thorough knowledge of a project best serves the owner and project team, and has the best competitive advantage when preparing a bid.

Common Cost Estimator Practice Traits

Awareness: The estimator should firstly consider the project scope and the level of effort and resources needed to complete the task ahead; the organization's financial capability, staff, and plant capacity (if working as an estimator for a construction company) to complete the project.

Consider the time allotted for the construction of the project in coordination with the owner's schedule needs.

Examine the general and special conditions of the contract and determine the effect these requirements have on indirect costs.

Consider alternate methods of construction for the projects. Review all sections of the drawings and division specifications to

ascertain an accurate perspective of the total project scope, level of design discipline coordination, adequacy of details, and project constructability.

Make other members of the project team aware of any problems with the project documents.

Communicate and coordinate information to other project team members in a timely manner.

Uniformity: The estimator should develop a good system of estimating forms and procedures that exactly meet the requirements of the project, and that is understood and accessible by all team members. This system should provide the ability to define material, labor hour and equipment hour quantities required for the project. Material, labor, and equipment unit costs are then applied to the quantities as developed in the quantity survey. Apply amounts for overhead and profit, escalation, and contingency in the final summaries.

Consistency: Use methods for quantity surveys that are in logical order and consistent with industry standard classification systems such as the UniFormat™ or CSI MasterFormat™ systems. These methods also must meet the specific need of the company or client. Use of consistent methods allows several

estimators to complete various parts of the quantity survey, or be continued later by another estimator. Consistency also aids the identification of cost increases and decreases in certain areas as the project progresses through the design stages. Combine these surveys into the final account summaries.

Verification: The method and logic employed in the quantity survey must be in a form, which can provide independent method of proof of the accuracy of any portion of the survey.

Documentation: Document all portions of the estimate in a logical, consistent, and legible manner. Estimators and other personnel may need to review the original estimate when the specific details are vague. The documentation must be clear and logical or it will be of little valve to the reader. Such instances may occur in change order preparation, settlements of claims, and review of past estimates as preparation for new estimates on similar projects.

Evaluation: When the estimate involves the use of bids from subcontractors, check the bids for scope and responsiveness to the project. Investigate the past performance records of subcontractors submitting bids. Determine the level of competence and quality of performance.

Labor Hours: The detailed application of labor hours to a quantity is primary in governing the accuracy and sufficiency of an estimate. The accuracy of the project's schedule and work force requirements are dependent on the evaluation and definition of the hours. The combined costs for worker's compensation, unemployment insurance and social security taxes are significant factors in the project costs. The most accurate method for including these costs is to define labor hours and wage rates; then apply percentages to the labor costs.

Valve Engineering: Structure the estimate to aid in researching and developing alternative methods that will result in cost optimization. These alternative methods can include different construction methodology, replacement materials, etc. Using the same level of detail in both the value engineering studies and the base estimate is extremely important. This provides a more precise comparison of costs for proposed alternate methods.

Final Summaries: Provide methods for listing and calculating indirect costs. Project scope governs the costs of overhead items such as insurance, home office plant, and administrative personnel. Determine these costs in a manner consistent with quantity survey applications. Consider other work in progress, and/or owner occupancy of existing space that may have a bearing on projected overhead costs. Determine amounts for performance bonding, profits, escalation, and contingencies.

Analysis:

Develop methods for analyzing completed estimates to ascertain if they are reasonable. When the estimate is beyond the normal range of costs for similar projects, research the detail causes for possible errors.

Develop methods of analysis of post-bid estimates to find the reasons for the lack of success in the bidding process.

Calculate the variation of the estimate from the low bid and low average bids.

Determine from an outside source if there were subcontract or material bids provided only to certain bidders.

Determine if bids were submitted by a representative number of contractors for the level of construction quality expected.

Determine if the low bidder may have made omissions in the estimate. Properly document this information for future use and guidance.

Conversion: Show estimating procedures that allow conversion of the estimate to field cost systems so management can monitor and control field activities. These procedures include methods of reporting field costs for problem areas. Make reports daily or weekly rather than at some point in time after the project is complete. Field cost reporting, when consistent with estimating procedures, enables estimators to apply the knowledge gained from these historical costs to

future estimates, and help train field personnel in labor hour and cost reporting that provide the level of accuracy required.

Change Orders: Apply the highest level of detail from information provided or available to the estimator. State quantities and costs for all material, labor, equipment, and subcontract items of work. Define amount for overhead, profit, taxes, and bond. Specific itemization of change order proposals is essential in allowing the client to determine acceptability. Upon approval, use the estimate detail as the definition of scope of the change order.

Levels of Estimate

As a project is proposed and then developed, the estimate preparation and information will change based on the needs of the Owner/Client/Designer. These changes will require estimates to be prepared at different levels during the design process with increasing degrees of information provided. It should also be noted that within each level of estimate preparation, not all portions of the design would be at the same level of completeness. For example, the architectural design may be at 80% complete while the mechanical design is only 50% complete. This is common through the design process, but should always be noted in the estimate narrative.

In addition to construction costs, estimates for process or manufacturing areas require information related to the involved processes such as product line capacity, process layout, handling requirements, utility requirements, materials and storage required, service requirements, flow diagrams, and raw materials access.

The following descriptions constitute the different levels of an estimate. Estimates within each of these levels may be prepared multiple times during the design process as more information becomes available or changes are made to the scope. As the level of the estimate increases it will become more detailed as more information is provided; "unknowns" are eliminated; fewer assumptions are made; and the pricing of the quantities become more detailed. Contingencies for the aforementioned will be reduced as more design documentation is produced.

The levels of the construction cost estimate correspond to the typical phases of the building design and development process and are considered standards within the industry. These levels are as follows:

Level 1 - Order of Magnitude

The purpose of the Level 1 estimate is to facilitate budgetary and feasibility determinations. It is prepared to develop a project budget and is based on historical information with adjustments made for specific project conditions. Estimates are based on costs per square foot, number of cars/rooms/seats, etc.

Project information required for estimates at this level usually might include a general functional description, schematic layout, geographic location, size expressed as building area, numbers of people, seats, cars, etc., and intended use.

Level 2 - Conceptual/Schematic Design

The purpose of the Level 2 estimate level is to provide a more comprehensive cost estimate to compare to the budgetary and feasibility determinations made at Level 1 and will be typically based on a better definition of the scope of work. An estimate at this level may be used to price various design schemes in order to see which scheme best fits the budget, or it may be used to price various design alternatives, or

construction materials and methods for comparison. The goal at the end of schematic design is to have a design scheme, program, and estimate that can be contained within budget. This estimate is often prepared in the UniFormat™ estimating system rather than the MasterFormat™ system, which allows the design team to easily and quickly evaluate alternative building systems and assemblies in order to make informed alternatives analysis decisions to advance the design progress. The Level 2 estimate is based on the previous level of information available at Level 1, in addition to more developed schematic design criteria such as a detailed building program, schematic drawings, sketches, renderings, diagrams, conceptual plans, elevations, sections and preliminary specifications. Information is typically supplemented with descriptions of soil and geotechnical conditions, utility requirements, foundation requirements, construction type/size determinations, and any other information that may have an impact on the estimated construction cost.

Design Development

Estimates prepared at Level 3 are used to verify budget conformance as the scope and design are finalized and final materials are selected. Information required for this level typically includes not less than 25% complete drawings showing floor plans, elevations, sections, typical details, preliminary schedules (finishes, partitions, doors, and hardware etc.), engineering design criteria, system single line diagrams, equipment layouts, and outline specifications.

The Level 3 estimate provides a greater amount of accuracy, made possible by better defined and detailed design documentation. Estimates at this phase may be used for value engineering applications before the completion of specifications and design drawings.

Level 4 - Construction Documents

Level 4 estimates are used to confirm funding allocations, to again verify the construction cost as design is being completed, for assessment of potential value engineering opportunities before publication of the final project design documentation for bids, and to identify any possible "design creep" items, and their costs, caused by modifications during the completion of the construction documents. This final construction document cost estimate will be used to evaluate the subcontract pricing during the bid phase. Level 4 estimates are typically based on construction documents not less than 90% complete.

Level 5 - Bid Phase

The purpose of this level estimate is to develop probable costs in the preparation and submittal of bids for contract with an Owner. In the traditional "design-bid-build" delivery system, this would be with 100% completed and coordinated documents. The Level 5 estimate will be used to evaluate sub-contractor bids and change orders during the construction process.

In other delivery systems, becoming more widely used, such as design-build or guaranteed maximum price, the bid could actually be prepared at an earlier level, often Level 3 or Level 4. In such an instance estimates are prepared as previously described along with progressive estimates as the design is completed. It should be stressed that when preparing a bid at a prior estimate level, it is very important to include a complete and thorough "Scope of Estimate" statement that would state clearly such items assumptions, allowances, documents used for the estimate, and contingency amounts included.

For a discussion of project delivery systems.

To explore the impact of various delivery systems on a specific project.

Various types of construction contracts include: Stipulated sum Lump sum unit price Cost plus a fee Design-build Bridging Cost plus a fee with a guaranteed maximum price (GMP) Turn Key

The transfer of the estimate information to the field cost control system provides management the opportunity to closely monitor and control construction costs as they occur. Computer estimating and cost control programs, whether industry-specific or general spreadsheet type, are especially valuable for rapid and efficient generation of both the estimate and actual construction cost information.

It should be noted that it is always good cost control practice to review and evaluate the final cost estimate vs. the actual bid. This exercise is not another level of estimate, but is a cost control mechanism and important data for estimating future projects.

D. Elements of a Cost Estimate

Quantity Takeoff: The foundation for a successful estimate relies upon reliable identification (takeoff) of the quantities of the various materials involved in the project.

Labor Hours: Labor hour amounts can be developed by crew analysis or applied on a unit man-hour basis. The use of a labor dollar per unit of work (ex: $15 per cubic yard for grade beams or $20 per cubic yard for walls) is only applicable when the cost history supports the data being used. The estimator must make allowance for the varying production capability that will occur based upon the complexity of a project.

Labor Rates: The labor rate is the cost per hour for the craftsmen on the project. To determine any craft rate, whether union or open shop, the estimator starts with the basic wages and fringe benefits.

To the wages and fringe benefits, the estimator must add payroll burdens. These are FICA (Social Security), FUI (Federal Unemployment Insurance), SUI (State Unemployment Insurance), WC (Worker Compensation) and others mandated by legislation and/or company operations. These burdens, plus the base wages and fringe benefits, determine the hourly cost of a craft classification (i.e., carpenter, pipefitter, etc.).

The hourly rate can also involve a mixed crew where a mix of different crafts for a work crew for the performance of the work.

Overtime or the lack of overtime is another consideration in determining the calculation of the hourly rates. A project that is scheduled for completion using a forty hour work week (Some areas may have a standard 35 hour week) will have a modest amount of overtime costs required in the estimate. A project that is scheduled for extended 50, 60 or even 70 hour work weeks will have a substantial amount included for overtime and loss of productivity.

Material Prices: Material prices, especially in today's current market, fluctuate up and down. The estimator must both understand and anticipate the frequency and extent of

the price variations and the timing of the buying cycle. Material prices may be affected by:

purchase at a peak or slack time of the year for the manufacturer material availability the size of the order the delivery timeframe requirement physical requirements for delivery, such as distance, road size, or site access payment terms and history on previous purchases sole-source items exchange rates (if the material will be imported into the U.S.)

Equipment Costs: Equipment rates depend on the project conditions to determine the correct size or capacity of equipment required to perform the work. When interfacing with other equipment, cycle times and equipment capacity control the costs on the project. Costs will also differ if the equipment is owned by the contractor as opposed to rented.

Subcontractor Quotes: A subcontractor quote, like the general estimate, contains labor, material, equipment, indirect costs, and profit. It is dependent upon having the quantities, labor hours, hourly rate, etc., prepared in a reliable manner just like any other part of an estimate. The amount of the subcontractor quote is also dependent upon the payment terms of the contract, and previous payment history between the subcontractor and general contractor. Bonding costs should also be considered.

Indirect Costs: Indirect costs consist of labor, material, and equipment items required to support the overall project.

For the owner: design fees, permits, land acquisition costs, legal fees, administration costs, etc.

For the contractor and subcontractor: mobilization, staffing, on-site job office, temporary construction, temporary heat/cooling, and temporary utilities, equipment, small tools and consumables, etc.

Profit Amount: Apply appropriate or contracted profit rate uniformly to all contractors and to original bid and change orders.

EMERGING ISSUES

Computers and Building Information Models (BIM)

Computers have played an increasingly larger role in cost estimation for complex calculations as the design and construction industry has become more computerized. For example, to undertake a parametric analysis (a process used to estimate project costs on a per unit basis, subject to the specific requirements of a project), cost estimators will often use a computer database containing information on costs and conditions of many other similar projects and geographic locations.

BIM is a simple concept—a master, intelligent data model, resulting in an as-built database that can be readily handed over to the building operator upon completion of commissioning. The BIM standard could someday integrate CAD data with product specifications, submittals, shop drawings, project records, as-built documentation and operations information, making printed O&M and Systems manuals virtually obsolete. The technology has moved forward, but the industry's ability to absorb these IT

advances has yet to change. Clearly, if BIM offers a genuine solution to reduce errors and rework, while improving building operations, it will eventually change the way all project team members develop and share information over facility life-cycle phases.

Sustainable Design and LEED® Certification

The GSA LEED® Cost Study for the U.S. General Services Administration defines costs associated with the U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED®) ratings. Two building types (new construction courthouses and Federal Building modernization) are modeled against two scenarios for each LEED® rating (Certification, Silver, Gold), identifying differential costs of construction, design, and documentation/submission requirements.

The newly issued GSA LEED® Applications Guide, a companion document to the GSA LEED® Cost Study, outlines an evaluation process in which the predicted first cost impacts of the individual LEED® prerequisites and credits (developed from the Cost Study) are used as a basis for structuring an overall LEED® project approach. The process also illustrates how LEED® criteria relate to existing GSA mandates, performance goals, and programmatic requirements.

Descriptions of LEED® cost impacts on private and non-federal public sector work may be found in various periodicals describing current projects. Coverage of sustainable and LEED® issues is becoming more frequent and is often the main focus of many periodical articles.

An article that discusses LEED® cost impacts and the participation of the cost estimator in the LEED® point evaluation process is The Cost of LEED Certification by Joseph Perryman (Design Cost Data (DCD), November 15, 2005). Mr. Perryman is Chairman of the ASPE Sustainability Special Interest Group, and a member of the Association for Project Management, the USGBC, the Royal Institution of Chartered Surveyors, SAVE International, and the Association for the Advancement of Cost Engineering.

RELEVANT CODES AND STANDARDS

The American Society of Professional Estimators (ASPE) recognizes the Certified Professional Estimator (CPE) as an individual trained in the estimating practices within the construction industry. Private and/or public sector owners can ensure a certain level of professionalism and ethics by stipulating that the cost estimator be a member of the ASPE. There are no legislative codes or mandated standards applicable to the cost engineering or cost estimating profession.

Architect's Role

Today, the required legal, technical, and cultural knowledge base has such breadth and depth that it is no longer in the best interest of the project for one discipline to hold, implement, and be responsible for all building-related knowledge, as did the Master Builder of old. Professional malpractice concerns have led liability insurance companies to encourage, even implicitly force, architects to limit activities to design. For example, "construction supervision" became "construction observation," moving the architect further away from the risks associated with construction activities.

According to some industry analysts, such as Carl Sapers, the architect's role has been further limited by the idea that buildings are commodities, consisting of assemblies of standard materials and systems best understood by their suppliers and constructors. New forms of project delivery, including "design/build", "bridging", and "construction management", come out of a belief that architects are no longer able to stay abreast of complex information in order to lead the design process on the owner's behalf. (Carl Sapers, "Toward Architectural Practice in the 21st Century," in Harvard Design Magazine, Fall 2003/Winter 2004)

However, this standardized approach to efficient building design is not necessarily synonymous with the requirements for whole building design. Integrated, high-performance design requires both efficiency and innovation. It requires a design process in which the users, owners, and project participants are all integral team members.

The Composite Master Builder

With whole building design, the project team can be guided once again by a collective vision. This structure, along with the process by which the design team works together, has been termed by Bill Reed as the "Composite Master Builder". The term recasts the historical single Master Builder as a diverse group of professionals working together towards a common end. The intention is to bring all of the specialists together, allowing them to function as if they were one mind. The process avoids, as Mario Salvadori says, the "reciprocal ignorance" of the specialists in the design and building field.

An innovative approach to efficiency: a prefabricated structure for an ecologically-sensitive site. Kingman Island Environmental Education Center competition finalist(Courtesy University of Maryland School of Architecture, Planning, and Preservation.)

The cast of specialists is potentially quite large, and depending on the complexity of the project, can include:

site professionals, such as planners, civil and environmental engineers, and landscape architects;

design team members such as programmers, architects, and interior designers; building systems experts, such as structural, mechanical, fire protection, and

building science and performance engineers; construction professionals, including cost estimators, project managers,

tradespeople, and craftspeople; owners, including financial managers, building users, and operations and

maintenance staff; and local code and fire officials.

The Team Needs a Leader

The legal obligations of the profession, comprehensive training in holistic problem-solving, and an understanding of broad cultural concerns make architects ideally suited for the leadership of design teams.

Architects in the United States have historically been bound by comprehensive legal requirements and responsibilities for the building design. They are legally obligated to safeguard the public health, safety, and welfare. This presumes that architects maintain at minimum a clear overview of the project team's work. Arguably, the most effective way to discharge this public duty is to oversee and coordinate the work of the project team.

The profession emphasizes comprehensive training in the arts and sciences, as well as a holistic approach to design problems. Architectural education teaches both abstract and concrete problem-solving. Its core skills are learned and re-learned, in an iterative process that incorporates history, theory, technology, and other social and cultural factors. Architects are both specialists and generalists, which ideally enables them to communicate effectively with other specialists while maintaining the "big-picture" view of the project goals.

In addition to health, safety, and welfare considerations, buildings incorporate the culture that created them. The built environment is both "mirror and lamp", shaping while acting as a repository of cultural meaning. As Churchill said, "We shape our buildings; thereafter they shape us." With their knowledge of the arts and culture, architects hold a comprehensive understanding of the project context and can help the design team move beyond mere problem-solving.

Education, Training, and Process for Whole Building Design

As leaders and participants in the design process, architects need to understand and work collaboratively with other disciplines. To this end, architects need to pursue education and training throughout their professional careers. Many excellent examples of interdisciplinary design studios exist in the United States. These studios involve students, faculty, practicing design and engineering professionals, and even clients and regulatory officials. Some studios participate in service-learning projects to build structures for deserving clients. Everyone involved—students, professionals and members of the community—benefits from the process itself, as well as the cross-pollination of ideas and techniques. Examples include Studio 804 at the University of Kansas School of Architecture and Urban Design, and Architecture 600/611 Comprehensive Studio and Advanced Technology at the University of Maryland's School of Architecture, Planning, and Preservation.

Continuing education is a lifelong endeavor for practicing architects and is mandated in many jurisdictions, as well as by The American Institute of Architects (AIA). Typically, this education involves technical training, management courses, legal and liability issues, and learning about new materials and products. The practice of seeking out training in the various aspects of leadership of an integrated design team, such as workshop facilitation, is not yet common. However, critical skills are needed to assume this role, which was addressed in a recent article in Environmental Building News. Current practitioners of integrated design, such as Terry Brennan of Camroden Associates, observe that architects have the intention to become cooperative but lack the skills. "The lead designer must be skilled in nurturing and giving form to the collective vision, rather than expressing his or her own vision. Not all architects are comfortable with this role, which is more akin to that of a midwife than to that of an individual artist." ( EBN , November 2004, "Integrated Design" feature article)

In daily practice, early and regular, structured interaction of the "Composite Master Builder," is critical to establishing a project vision and maintaining momentum throughout the design and construction process. Activities might include charrettes, workshops, peer review, and post-occupancy review.

Until recently, most building codes have been prescriptive, effectively casting design professionals in the role of negotiators between the owner's ideas and the realities of codes. High-performance, integrated building design recently started leading design teams away from this "just barely legal" approach. As a tool to aid in this process, the new performance-based building codes give the design team more flexibility in meeting requirements.

1. List of Codes

The international Code Council (ICC) was formed from the joining of publishers of National and Standard Building Codes, Building Officials and Code Administrators International, the Southern Building Code Congress International, and the International Conference of Building Officials. The result of their merging was the International Code Series—part of the U.S.'s first unified comprehensive and coordinated building codes.

A. U.S. Code Organizations:International Code Council (ICC)International Conference of Building Officials (ICBO), member of ICCSouthern Building Code Congress International, Inc. (SBCCI), member of ICCInternational Association of Plumbing and Mechanical Officials (IAPMO)National Fire Protection Association (NFPA)Underwriters Laboratories (UL)

B. Codes:Americans with Disabilities Act Guidelines (ADAAG)CABO One and Two Family Dwelling CodeInternational Code Series:International Building Code (IBC)International Energy Conservation Code (IECC)International Fire Code (IFC)International Fuel Gas Code (IFGC)International Mechanical Code (IMC)International Plumbing Code (IPC)International Property Maintenance Code (IPMC)International Residential Code (IRC)National Building Code (BOCA NBC)National Fire Protection Association codes (NFPA)National Electric Codes (NEC)Uniform Building Code (UBC)

2. List of Standards and Organizations

Many of these organizations have voluntary standards for quality assurance. Others publish standards that are referenced by the LEED Green Building Rating Guide, for meeting requirements of various credits.

American Forest and Paper Association (AFPA) (formerly the National Forest Products Association)

American Institute of Steel Construction (AISC)American National Standards Institute (ANSI)APA - The Engineered Wood Association (APA)

American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE)ASTM InternationalArchitectural Woodwork Institute (AWI)American Wood Council (AWC)Federal Emergency Management Agency (FEMA)Federal Energy Management Program (FEMP)Federal Housing Administration (FHA)Forest Stewardship Council (FSC)Illuminating Engineering Society of North America (IESNA)International Performance Measurement and Verification Protocol (IPMVP)National Fire Protection Association (NFPA)National Association of Home Builders (NAHB)National Institute of Standards and Technology (NIST)National Institute of Building Sciences - Construction Criteria Base (CCB)Underwriters Laboratories (UL)U.S. Department of Agriculture, Forest Service, Forest Products Laboratory (FPL)U.S. Department of Commerce, National Technical Information Service (NTIS)U.S. Department of Energy (DOE)U.S. Environmental Protection Agency (EPA)U.S. Department of Housing and Urban Development (HUD)

3. Federal and Non Government Databases for Standards and Regulations

Whole Building Design Guide—Mandates/ReferencesWhole Building Design Guide—Construction Criteria Base

Professional Associations

Association of Collegiate Schools of Architecture (ASCA)The American Institute of Architects (AIA)American Institute of Architecture Students (AIAS)National Council of Architectural Registration Boards (NCARB)National Architectural Accrediting Board, Inc. (NAAB)

Related Organizations

Architecture Research Institute, Inc.Association for Computer Aided Design in Architecture (ACADIA)Building Owners and Managers Association (BOMA)Congress for the New Urbanism (CNU)Department of Energy (DOE):Energy SourcesEnergy EfficiencyNational Association of Homebuilders (NAHB)National Association of the Remodeling Industry (NARI)National Organization of Minority Architects (NOMA)Sustainable Buildings Industry Council (SBIC)Urban Land Institute (ULI)U.S. Green Building Council (USGBC)

Today's HVAC&R engineer, or mechanical engineer of record (MER), continues to be a steward of the basic discipline issues identified by Mr. Wilson nearly 100 years ago.

Roles have expanded, though, to address more modern quality of life issues. ASHRAE offers the current vision of the MER's stewardship responsibilities: to improve the quality of life by helping keep indoor environments comfortable and productive; by helping to deliver healthy food to consumers; and by helping to preserve the outdoor environment.

As part of a holistic controlled environment design solution, the MER is responsible for addressing seven major processes. These are:

1. Heating—the addition of thermal energy to maintain space or process conditions in response to thermal heat loss

2. Cooling—the removal of thermal energy to maintain space or process conditions in response to thermal heat gain

3. Humidifying—the addition of water vapor to maintain space or process moisture content

4. Dehumidifying—the removal of water vapor to maintain space or process moisture content

5. Cleaning—the process of removing particulate and bio-contaminants from the conditioned space.

6. Ventilating—the process of providing suitable quantities of fresh outside air for maintaining air quality and building pressurization.

7. Effectiveness—the process of achieving the desired thermal energy transfer, humidity control, filtration, and delivery of ventilation air to the breathing zone of the occupied space in accordance with required needs.

It is important for the MER to be involved early in the project, even as early as the programming stage, so that mechanical system space issues and facility energy budgets can be evaluated and integrated into the design process before building construction elements, configurations, and orientations are finalized (see also WBDG High-Performance HVAC). A few critical issues that need to be considered early are:

Financial Focus: Will the project be a code minimum type facility or will total ownership cost perspectives be considered that balance capital first costs against long-term ownership and operating costs?

Owner Sophistication: The MER needs to understand the abilities of the owner and keep these in mind as mechanical system architecture issues are considered. The best of design solutions aren't much good if operators do not understand how to correctly operate or control the equipment.

Operations and Maintenance : No matter what level of system complexity is applied, it is imperative that suitable space be made available for equipment without compromising performance or maintenance access. A good MER will understand the requirements published in equipment installation manuals and focus on providing prescribed minimum service and operating considerations in the planning of a facility layout.

Before any equipment selections can be finalized, the MER will need to perform a thermal load calculation for the developing facility based on internal and external influencing factors. In many cases, this activity will be expanded to include analysis of comprehensive energy models. These models will foster dynamic integration opportunities whereby the design team and owner can evaluate the impacts of trade-offs between facility construction elements, mechanical system alternatives, and available operating efficiencies. Load calculations can be utilized for any or all of the following design activities:

A. Defining the basic load dynamics B. Evaluating solution alternatives via life-cycle analysis C. Optimizing system performance D. Selecting final HVAC equipment E. Establishing energy budgets for owners F. Verification of proposed equipment performance G. Commissioning Design Intent for seasonal comparison

The MER will be responsible for securing/developing the following fundamental information from the Owner and design team members:

Basic Load Calculations: Establish summer/winter design weather conditions paying particularly

close attention to regional weather issues and impact on humidification/dehumidification considerations.

All elements of the building envelope must be identified so that thermal energy loss/gain can be determined. Reference should be made to ASHRAE Standard 90.1 for regionally documented envelope construction minimum thermal quality considerations.

Orientation of walls and roofs need to be defined so that sun angle impacts can be evaluated.

The composite construction of all walls, roofs, and floors needs to be defined so that thermal transfer calculations can be performed. This information will also be useful when a dew point analysis is performed on the envelope.

Thermal mass and color of walls and roofs need to be defined so that thermal time lags and radiation absorption can be evaluated.

Fenestration U-values and solar heat gain coefficients need to be defined.

External/internal shading provisions need to be defined that may impact fenestration heat gain.

Lighting: Lighting densities and ballast loss factors need to be mapped

per individual space. Maximum densities are identified for individual space types in ASHRAE Standard 90.1.

Opportunities to capture natural light (Daylighting) and apply occupancy sensing techniques to reduce light heat gain need to be explored.

Basic internal sensible heat gain allowances for receptacle loads need to be established.

Miscellaneous sensible and latent heat gain values need to be identified for special circumstances.

People contributions: The total number of people and the occupancy usage profiles

need to be established. The activity levels of people need to be identified.

Ventilation : For a given space, the area factor and people factor ventilation

rate components need to be calculated per ASHRAE Standard 62.1.

Depending on HVAC system architecture employed, critical space calculations may need to be performed to adjust ventilation quantities to ensure adequate outside air is being provided to occupied spaces during all system fluctuations.

Calculate all building exhaust requirements and compare to minimum required outside air ventilation rates. The overall impact of building pressurization dynamics must be evaluated for the facility, for seasonal conditions, and for regional locations. The MER must fully understand how moisture and thermal gradients work with the building envelope construction and what influence infiltration/exfiltration has on condensation potential.

Basic system zoning: Identify spaces and zones.

Establish summer/winter design temperature set-point conditions and dead-band ranges per thermal comfort recommendations of ASHRAE Standard 55.

Energy Modeling: Establish realistic average weather profiles for project location. Define realistic 24-hour usage profiles for the entire calendar year

taking into account workdays, weekends, holidays, etc. Obtain current rate structures from utilities. Define accurate equipment power consumption paying particular

attention to part load efficiencies. Life-Cycle Analysis:

Define capital cost impacts of equipment and system alternatives. Determine client applicable time value of money evaluation

parameters. Determine accurate maintenance costs for equipment and system

alternatives.

Once the facility thermal issues are identified, the MER will be faced with application decisions to find appropriate, constructible, controllable, affordable, and maintainable HVAC&R solutions. These solutions must be integrated and coordinated with parallel design and planning activities of fellow design team members. While not totally encompassing, the following discipline considerations need fundamental attention:

Architectural Interaction:

Impacts By Impacts To

Equipment room locations, accessibility, and size

Location and appearance of air distribution devices

Floor to floor height, depth of structure, ceiling height, and available utility space in ceiling cavity

Component aggregation and location of building envelope elements

Location of Life Safety features such as fire and smoke rated construction and the impacts on HVAC constructability

Location and construction of noise sensitive areas

Selection of interior finishes and VOC impacts.

Location of equipment

Orientation of the building

Structural Engineering Interaction:

Impacts By Impacts To

Type of construction: steel, concrete, wood, etc.

Foundation design

Location, weights, and support/attachment of equipment

Fireproofing techniques

Seismic criteria

Civil Engineering Interaction:

Impacts By Impacts To

Location of site utilities

Siting and landscaping impacts on thermal loads and noise trespass

Size and location of utility connections

Electrical Engineering Interaction:

Impacts By Impacts To

Size of available power service Layout of design Gen-set ventilation, heat removal,

and fuel support requirements

Location of electrical infrastructure: switchboards, panels, feeders, etc.

Equipment power requirements Coordination of power hook-up and

disconnecting means Coordination of Fire Alarm shut-

down and smoke detectors

Location of duct, pipe, and air distribution

Plumbing Engineering Interaction:

Impacts By Impacts To

Type and capacity of heat generation plant for hot water heating

Location of plumbing infrastructure: equipment, piping, etc.

Make-up water requirements and backflow protection

Condensate drainage disposal requirements

Location of duct, pipe, and air distribution

Fire Protection Engineering Interaction:

Impacts By Impacts To

Fire pump ventilation, heat removal, and fuel support requirements

Location of sprinkler and standpipe infrastructure: equipment, piping, heads, etc.

Location of duct, pipe, and air distribution

EMERGING ISSUES

HVAC systems have increased in complexity over the years. While the fundamentals track to the basics developed by the pioneers in the early 20th century, the MER has many more collateral design issues and liability concerns to consider today.

A. Energy

The energy crisis of the 1970s initiated a new focus on energy efficiency and shift to part-load design dynamics. Energy wasteful solutions have become obsolete. Designing systems with a peak load only perspective has become obsolete. Managing peak loads to reduce peak energy demand has become essential. The MER must understand the impacts of equipment part-load performance and overall, integrated system performance.

Energy codes and standards have aggressively forced equipment manufacturers to improve the efficiency of equipment and integrated systems. Renewable energy solutions have become, for some applications, economically feasible considerations. Owners have become total ownership cost savvy and understand the bottom line impact of energy budgets and energy consumption profiles. Dependence on fossil fuel based energy solutions is becoming a concern. The MER must recognize the impact of the energy issue and respond to energy efficient and renewable solutions.

B. Energy Modeling

Energy modeling is the process of using scientific methods and analytical tools to estimate the energy consumption patterns of a given facility, constructed of given materials, located in a given climate zone and operated according to given schedules. These tools and methods range from simple hand calculations and spreadsheets to the most sophisticated software packages designed to consider numerous building configurations, denote multiple zones, model multiple systems with many varied hours of operation, and integrate with/to Building Information Models.

Energy modeling should be utilized to help integrate and optimize a building's energy consuming systems' performance over the expected life cycle of the facility. Those systems include, but are not necessarily limited to, the building envelope, HVAC&R systems, area lighting, water heating, pumping, elevators and personnel transportation devices, process and plug type power loads. Plug type loads include items such as task lights, computers, space heaters, appliances, TVs, etc.

Energy modeling may also be required if it becomes necessary to value engineer a project after the design phase is complete. Simple substitutions of less costly materials, products, equipment, or systems at this stage of a highly integrated building design may have serious and profound negative effects on the building's future energy and environmental performance if not properly analyzed prior to acceptance.

During the programming and/or schematic design phases the HVAC&R engineer should be prepared to assist the architectural design professional and Owner in optimizing a building's envelope and orientation design long before HVAC&R system selections and equipment alternatives are considered. Simple shoe box type models considering the buildings basic mass and scale may be quickly setup at this phase of design and zones with similar thermal characteristics may be assigned within the building. Consideration should be given to the building envelope materials (exterior wall cladding, wall insulation, roof materials and insulation, fenestration materials), orientation, cost of

materials, and local climate. During this phase, a baseline model should be created with which to compare any alternative or proposed designs. The baseline model may be a code required minimum building, a building similar to one that the Owner is moving out of, or a building similar to one that the Owner typically constructs.

Moisture Control

Moisture control has become a significant liability issue for the MER. A very negative trend has been developing in the industry recently whereby buildings are making occupants sick due to growth of mold. There is no one reason to explain why such a proliferation of mold contamination cases has blossomed, but there are some fundamental factors that the MER must keep in perspective while designing a facility, such as:

All water generation sources inside the facility need to be understood and minimized.

Construction of the building envelope must be properly applied to the climate zone in question. The relationship of vapor retarders and air barriers needs to be correctly understood.

All possible relative building air pressure relationships (internal and external) need to be understood to avoid bringing undesirable, untreated moisture into the facility.

D. Ventilation and Dedicated Outside Air Systems (DOAS)

Application of ASHRAE Standard 62.1 may create some difficult design challenges for the MER. The correct outside air ventilation requirements for a given space/zone/facility layout may very easily exceed the summation of the simple people and area factor prescribed ventilation rates when ventilation effectiveness is taken into account. When multiple spaces are included into the same zone, calculations must be performed to identify the correct ventilation rate that ensures adequate distribution to all spaces and zones for all operating conditions. Depending on the zoning configuration, the multiple space calculation corrections can increase the minimum required outside air quantity.

The utilization of excessive outside air will have a significant impact on cooling/heating loads and the sizing/selection of equipment and plant solutions. Additionally, depending on the climate zone in question, an undesirable high quantity of moisture could be coming into the building. As latent cooling requirements increase, sensible heat ratios start to decrease. As sensible heat ratios drop, the proper application of equipment to maintain space temperature and humidity becomes problematic.

The increased outside air quantities also impact the minimum setting on variable volume terminal units. It is conceivable that the terminal unit minimums could be so high that the need for constant reheat may be required and the benefit of having the all air VAV system becomes an energy liability.

DOAS systems provide a creative solution that addresses multiple issues. For example: The DOAS approach allows the outside air latent load to be decoupled from the

space sensible load. The outside air path can be conditioned based on dew point control to deliver neutral or cold air to a parallel space sensible cooling system. Space temperature can then independently be controlled by the sensible cooling system.

The DOAS air path is 100% outside air, not mixed, and can be delivered at the prescribed quantity directly to the space based on the people and area factor ventilation rates. Multiple space calculations do not need to be considered.

Since no mixing is involved, ventilation rate delivery to the space/zone can actually be verified and continuously monitored.

The new requirement in ASHRAE Standard 62.1 that requires occupied spaces be held below 65% relative humidity now becomes achievable at part-load cooling conditions.

The problems encountered with scroll compressor DX VAV units cycling off when leaving air temperature is satisfied and raw outside air is pulled across a de-active coil, are minimized. Additionally, the phenomena of moisture on the coil and in the drain pan being re-evaporated back into the unconditioned air path can be eliminated.

Building Information Modeling (BIM)

BIM is the concept of using truly intelligent 3D modeling software to create optimized, efficient, and environmentally friendly building designs. The concept has been around since the advent of the first computer-aided drafting (CAD) system. However, the industry is still a decade or more away from having commercially available software that integrates the needs of every design and construction discipline as well as the ownership, operation, and maintenance needs of the building owner throughout the useful life of a facility.

For example, a complete BIM solution would allow the Architect to create an intelligent 3D model of a building, its site and location. That model would include the aesthetic, physical, and thermal properties of each component as well as specification and cost data. Then the Civil Engineer would use a software interface to allow the design of the site and analysis of all utilities and drainage systems involved. Similarly, the Structural Engineer's software would allow him to use the characteristics from the Architect's model to size structural members and properly reinforce the structure based on each component's physical characteristics and the project's geographic location. The MER would interface with the Architect's model to seamlessly generate Energy Models and Life-Cycle Cost Analysis of the building's envelope and energy consuming systems, and so on for all other disciplines involved. Finally, after all design is complete, the original modeling software would compile the data from each discipline and generate a BIM and a set of digital Construction Documents for use to construct the facility.

Use of the BIM would continue into the bidding phase by interface with a contractor's cost estimating, scheduling, and project management software and manufacturers' material, fabrication, and cost databases to generate optimized cost estimates and construction schedules. During construction, the model would be continually updated to as-built conditions including integration of manufacturers' complete operations and maintenance data and instructions. At completion of construction the Building Information Model would be turned over to the Owner for interface with facility management software to optimize the operation and maintenance of the facility for the duration of its life.

F. Commissioning

See Building Commissioning.

G. Performance-Based Building Codes

See Fire Protection Engineering in the Design Disciplines section for a discussion of Performance-Based Building Codes.

H. Acoustics

The fundamentals of equipment sound power levels, transmission paths, and resulting sound pressure readings go beyond the application and understanding of basic thermodynamics. The MER should have sufficient understanding of acoustics to be able to benchmark the sound quality of the equipment applied as the design solution and attenuate sound paths accordingly to the acoustical criteria for the occupied spaces.

While acoustical design techniques really haven't changed, the issuance of ANSI 12.60-2002 has changed the integrated design dynamic. A standard of care document is now in print that details sound quality features for school environments. Successful compliance with this new standard will require a concentrated coordination effort between mechanical and general construction interest. All sound transmission paths (discharge, radiated, breakout, etc.) must be analyzed to show anticipated space sound pressure based on equipment selection sound power source energy. Equipment locations, equipment operating points, transmission path construction, end room reflectance, and resulting sound pressure are all variables that the MER needs to understand and manipulate.

I. High Density Data Servers

Facilities are becoming "smarter" and fully networked. This high-tech trend has created a new challenge for the MER. Communication and data storage servers are adding significant sensible cooling loads to the indoor environment. As server technology improves to provide better speed and capacity, the sensible heat rejection load component keeps rising. Recent studies show the heat rejection densities for server equipment doubling, maybe even tripling, in just the next five year window. Rarely has the MER been faced with a commercial design challenge wherein the HVAC infrastructure may be obsolete so quickly. High density loads, hot/cold aisles, and phased capacity methodology are new issues that the MER will have to address. See Information Technologies Engineering.

Indoor Air Quality (IAQ)

IAQ is a broad issue that requires a total team stewardship; it is not just an HVAC&R issue. Addressing IAQ issues requires a holistic, integrated response from the owner, the entire design team, and the operation/maintenance team. Occupant discomfort and building related illness are frequent complaints that owners must respond to. Discomfort factors can include: temperature, humidity, drafts, indoor pollutants, biological agents, and non-biological particles and fibers. Building related illnesses can include hypersensitivity, pneumonitis, and Legionnaire's disease. Common health complaints can include eye/nose/throat irritation, headaches, fatigue and lethargy, upper respiratory symptoms, and skin irritation and rashes. See Indoor Air Quality and Mold Prevention of the Building Envelope.

The MER should be cognizant of the following issues: Volatile Organic Compounds (VOC) pose a source challenge based on the variety

of source opportunities and possible chemical introductions to the building. Sources can include: construction materials, furnishings, cleaning products, copiers/printers, environmental tobacco smoke, people, personal hygiene products, air fresheners, and outdoor air. Consideration should be given to elimination, substitution, or containment of VOC generation sources.

Effective temperature and humidity control are achievable with the application of appropriate systems, effective air distribution, and proper control sequences. Humidity levels can negatively impact mucous membranes (too low) and upper

respiratory tracts (too high). The MER should also consider that high humidity levels support the growth of mold and bacteria. An interesting new provision in ASHRAE Standard 62.1 is the addition of a maximum humidity level of 65% for occupied spaces.

The design of air systems must factor in the possible spread of airborne infectious agents, such as viruses and bacteria, generated by the occupants inside the building. As part of an appropriate risk management analysis, infrastructure solutions such as extent of filtration, UV light treatment, ventilation effectiveness, air changes, and building pressure control need to be investigated.

The building or systems within it may be sources of infectious agents such as fungus or bacteria. These sources can contribute to significant invasive diseases such as aspergillosis, legionellosis, and histoplasmososis. Minimizing the introduction of moisture into the building or ventilation system is critical to the mitigation of these deadly diseases.

The growth and support of non-infectious biological agents (fungus, bacteria, dander, and allergens) needs to be minimized. Locations of outside air ducts need to be optimized with site dynamics. Sources of moisture generation and intrusion need to be eliminated. Maintaining filtration and proper operation of equipment become critical factors.

Non-biological particles must be considered. Sources include the quality of the outside air available, tobacco smoke generation, combustion products, process related dust/fume generation, and material generated particles. Construction activities can be a significant source of fine and large particles. Early occupancy of new construction can present a liability to the owner. Protection of buildings under renovation becomes a critical exercise.

Inorganic gases such as carbon monoxide, nitrogen oxides, ozone, and radon can all have significant impact on occupants. These gases can be generated internally from smoking or combustion processes, operation of copiers and printers, operation of air cleaners, and poorly vented combustion equipment. Gases can also be introduced from the exterior via poor outdoor ventilation air, or in the case of radon, drawn up through the soil beneath and around the building.

Individual susceptibility, the "human factor", can vary from person to person. Factors such as allergic sensitivity, prior exposure, stress, and gender all play a role in how individuals react to and are impacted by IAQ issues.

(Source: Indoor Air Quality - Position Document, ASHRAE, 2005)

M. Sustainable/Green Building Design

Leadership in Energy and Environmental Design (LEED) is no longer a design and construction industry buzzword, catch phrase, or fad. As of fall 2005, there were over 21,000 LEED Accredited Professionals, 2,100 LEED registered projects, and almost 300 LEED certified projects located in 50 states and 14 countries encompassing more than 300 million gross square feet of buildings.

LEED is a Green Building energy and environmental performance rating system conceived by the United States Green Building Council (USGBC) in 1991 and formally introduced to the design and construction industries in 1993. Currently there are over 5,500 members of the USGBC. Members include owners, manufacturers, universities, design professionals, and local/state/federal agencies. The USGBC has partnered with the AIA and ASHRAE along with other organizations to help refine current rating systems and develop future rating systems that are truly consensus based.

The LEED System is not a code or standard. It is rather a voluntary method by which building owners may demonstrate their commitment to energy efficient and environmentally friendly building design, construction, operations, and maintenance practices that are better than minimum code requirements. The Green Building Initiative has a similar rating program called Green Globes. Additionally, many state and local government agencies have regionally customized rating systems that outline high-performance building roadmaps.

A question often asked by clients is: What is the cost associated with designing and building high-performance green buildings? For federal building applications see the GSA LEED® Cost Study and Applications Guide. Although the first cost of designing and building is often more, the payback for owning and operating a high-performance building is typically 5 years or less. Since employee salary costs are typically ten times the cost of energy and operating costs of a building, paybacks may be much less when the increased productivity and lower absenteeism often associated with working in a high-performance building are considered.

The "Green Building" movement has brought the MER to the forefront within the building design team by emphasizing skills in Building Information and Energy Modeling. The specialized knowledge of the MER is critically important to the success of the high-performance project as IAQ, energy, acoustical quality, building security/safety, and environmental perspectives are constantly evaluated.

Specifications

With the release of MasterFormat 2004 Edition , the A/E community, constructors, manufacturers, and owners have an entirely new organizational structure for preparing project manual content. The old Division 1-16 specification system has been completely replaced by a system that has 2 main Groups, 5 Subgroups, and 50 total Divisions.

The MER is significantly impacted by this change as the familiar Division 15 - Mechanical does not exist anymore. The same can be said for the old Division 16 - Electrical. Plumbing, mechanical, and electrical systems for facilities have been organized into a new Group titled Specifications and a new Subgroup titled Facility Services. An excerpt from MasterFormat 2004 Edition showing the facility oriented content is organized as follows:

Facility Services Subgroup:

Division 20 - (Future) Division 21 - Fire Protection Division 22 - Plumbing Division 23 - Heating, Ventilating, and Air-Conditioning (HVAC) Division 24 - (Future) Division 25 - Integrated Automation Division 26 - Electrical Division 27 - Communications Division 28 - Electronic Safety and Security

Division 29 - (Future)

(Source: MasterFormat 2004 Edition, CSI, 2004)

O. Building Health and Safety—Extraordinary Incidents

Building Health and Safety—Extraordinary Incidents

The concept of "extraordinary incidents" creates a paradigm shift in thinking for the MER and the resulting approach to facility design. Events such as war, terrorism, accident, or natural disaster need to be considered while planning for the occupant safety and protection of basic air, water, and food sources in the built environment.

The owner and design team now must consider and evaluate levels of risk, vulnerability, and acceptable vulnerability. Risk and vulnerability vary depending on the type of facility, function, accessibility, and location. Risk management techniques, which have not been a traditional part of HVAC&R design logic, must now be employed to determine potential compromise issues and to identify measured design solution responses. Theses issues are discussed in the document Risk Management Guidance for Health, Safety, and Environmental Security under Extraordinary Incidents, published by ASHRAE in 2003.

Extraordinary incident design response will have significant impact on building system design, construction, and operation. Consider the following points:

Interdependence of building systems must be understood so that the relationships of impacts can be planned for once any one system fails.

The extent and cost of redundant and backup systems needs to be determined. The health and comfort of occupants should not be compromised at the expense

of addressing vulnerability. Application of high efficiency particulate filtration (MERV 14 or greater), gas and

vapor removal technology, and UV light treatment can provide significant levels of protection. Risk assessment and economic analysis will determine the extent to how extensive this response can be implemented.

Outdoor air intakes need to be strategically located to minimize potential intake of airborne biological contaminants.

Building envelopes need to be designed with appropriate air/moisture barriers and positive building pressure control provisions to minimize infiltration of airborne biological contaminants.

HVAC control sequences of operation need to be defined for normal and extraordinary events. Infrastructure must be in place to provide transitions between operating modes.

Commissioning becomes a critical event now. The proper operation of equipment during an extraordinary event must be verified and understood.

RELEVANT CODES AND STANDARDS

Air-Conditioning and Refrigeration Institute (ARI):ARI Standard 260-2001: Sound Rating of Ducted Air Moving and Conditioning EquipmentARI Standard 300-2000: Sound Rating and Sound Transmission Loss of Packaged Terminal

EquipmentARI Standard 350-2000: Sound Rating and Non-Ducted Indoor Air-Conditioning EquipmentARI Standard 410-2001: Forced-Circulation and Air-Cooling and Air-Heating CoilsARI Standard 430-1999: Central Station Air Handling UnitsARI Standard 550-2003: Standard or Water Chilling Packages Using the Vapor Compression

CycleARI Standard 880-1998: Air TerminalsARI Standard 885-1998: Procedure for Estimating Occupied Space Sound Levels in the

Application of Air Terminals and Air OutletsARI Standard 890-2001: Rating of Air Diffusers and Air Diffuser Assemblies

Air Movement and Control Association (AMCA):AMCA Standard 99-0021-01: The Fan LawsAMCA Standard 210-99: Laboratory Methods of Testing Fans for Aerodynamic Performance

RatingAMCA Standard 300-05: Reverberant Room Method for Sound Testing of FansAMCA Standard 301-05: Methods for Calculating Fan Sound Ratings from Laboratory Test

DataAMCA Standard 330-97: Laboratory Methods of Testing to Determine the Sound Power in a

DuctAMCA Standard 500-D-98: Laboratory Methods of Testing Dampers for RatingAMCA Standard 500-L-99: Laboratory Methods of Testing Louvers for RatingAmerican National Standards Institute (ANSI):ANSI S12.60-2002: Acoustical Performance Criteria, Design Requirements and Guidelines for

SchoolsAmerican Society of Heating, Refrigerating, and Air-Conditioning Engineers, Inc. (ASHRAE):ASHRAE Standard 15-2004: Safety Standard for Refrigeration SystemsASHRAE Standard 15 Users ManualASHRAE Standard 34-2004: Designation and Safety Classification of RefrigerantsASHRAE Standard 52.2-1999: Method of Testing General Ventilation Air Cleaning Devices for

Removal Efficiency by Particle SizeASHRAE Standard 55-2004: Thermal Environmental Conditions for Human OccupancyASHRAE Standard 62.1-2004: Ventilation for Acceptable Indoor Air QualityASHRAE Standard 62.1 Users ManualASHRAE Standard 90.1-2004: Energy Standard for Buildings Except Low-Rise Residential

BuildingsASHRAE Standard 90.1 Users ManualASHRAE Standard 126-2000: Method of Testing HVAC Air DuctsASHRAE Standard 135-2004: BACnet - A Data Communication Protocol for Building

Automation and Control NetworksASHRAE Standard 140-2004: Standard Method of Test for the Evaluation of Building Energy

Analysis Computer ProgramsASHRAE Standard 147-2002: Reducing the Release of Halogenated Refrigerants from

Refrigerating and Air-Conditioning Equipment and SystemsInternational Code Council (ICC):International Building Code, 2003International Energy Conservation Code, 2003International Fuel Gas Code, 2003International Mechanical Code, 2003National Fire Protection Association (NFPA):NFPA 70: National Electrical CodeNFPA 90A: Standard for the Installation of Air Conditioning and Ventilating SystemsNFPA 101: Life Safety CodeNFPA 900: Building Energy CodeNFPA 5000: Building Construction and Safety Code

This resource page examines both a description of a Building Information Model (BIM) as well as the collaborative effort currently underway to develop a National BIM Standard.

A BIM is a digital representation of physical and functional characteristics of a facility. As such it serves as a shared knowledge resource for information about a facility forming a reliable basis for decisions during its life-cycle from inception onward.

A basic premise of BIM is collaboration by different stakeholders at different phases of the life-cycle of a facility to insert, extract, update or modify information in the BIM to support and reflect the roles of that stakeholder. The BIM is a shared digital representation founded on open standards for interoperability.

Some have identified BIM as only 3D modeling and visualization. While partially true, this description is limiting. A more useful concept is that a BIM should access all pertinent graphic and non-graphic information about a facility as an integrated resource. A primary goal is to eliminate re-gathering or reformatting of facility information; which is wasteful. BIM standards have many objectives but one of the most important is to improve business functioning so that collection, use and maintenance of facility information is a part of doing business by the authoritative source and not a separate activity.

DESCRIPTION

This description contains two sections. The first section describes desirable BIM characteristics and the second section describes the effort underway to develop a standard for information sharing that will help weave all stakeholders into a common fabric.

Section 1 - Building Information Model Ideals

The acronym "BIM," is historically linked in the minds of many to 3-dimensional and now 4 (time) and 5 (cost) dimensional virtual modeling of buildings. BIM, however, has the capability and even the responsibility to be much more.

"Building" in this usage is a noun referring to the structure more than the process and accordingly, current BIM examples tend to be virtual models of individual or small clusters of buildings executed in proprietary software for the purpose of supporting the design, detailing and construction phases of the lifecycle. Used within this scope, BIM speaks primarily to architects, architectural engineers, specifiers, estimators, scientists interested in performance modeling, constructors and construction vendors, computer application vendors interested in this business space, and owners as they participate in the new-building development process. The future of BIM modeling is to expand the information model to include more of the lifecycle phases (ie: real property commerce, maintenance and operations, environmental simulation, etc.), to standardize lifecycle process definitions and associated exchanges of information, and to standardize information content so that meanings and granularity are clear and consistent. This expanded scope definition will make BIM useful to a wider community including, for example, real property managers, appraisers, brokers, mortgage bankers, facility assessors, facility managers, maintenance and operations engineers, safety and security personnel as incident responders, landscape architects, infrastructure engineers and operators, and others outside the business verticals associated with new building design and construction.

Although BIM applications and practices in current use are vastly superior to manual and 2D-only CAD methodologies, current usage of BIM technologies and techniques must be improved further. Currently, processes and content are locally negotiated on a project-by-project basis and data sets (i.e.: models) are not necessarily capable of being used for different purposes through unassisted machine-to-machine and application-to-application exchanges. To realize needed end-to-end efficiencies in the capital facilities industry these are the characteristics that are needed in BIM methods.

Ironically, many BIM applications are already capable of supporting standardized interoperable processes and content if they existed. But in the absence of standards and associated best practice definitions, this support is only utilized on an ad-hoc,

project-by-project basis and often is re-negotiated and/or recreated for each services contract and/or project.

It is true that associating BIM with the development and use of 3D virtual building modeling techniques and technologies can yield very productive results. However, when used in this context, BIM tends to be focused on data and technology standards during design and construction and may not fully realize the potential for information-based, interoperable business processes related to "building" (the verb).

Section 2 - Implementing BIM - The National BIM Standard

The work of the National BIM Standard Committee (NBIMS), a committee of the National Institute for Building Sciences (NIBS), is to knit together the broadest and deepest constituency ever assembled for the purpose of addressing the losses and limitations associated with errors and inefficiencies in the building supply chain¹.

The current NBIMS Charter signatories (a list of which can be seen at the NBIMS web site) represent most, of the active end-user constituencies as well as many of the professional associations, consortia, and technical and associated services vendors who support them.

Several organizations have initiatives underway to develop data technology (i.e., interfaces, encodings, schema, etc., that enable different technologies to "plug and play"), generic business process workflows and content standards. One of the most important tasks for NBIMS is to coordinate these efforts and harmonize work between all organizations with similar products and interests. Many professional organizations are actively endorsing NBIMS as well as providing subject matter expertise and important development resources. In addition, over 300 applications now support IFC's and most BIM application vendors have indicated their support for BIM standards and are participating on the committee both in an advisory capacity and through participation in test bed demonstrations. A list of the active organizations are found at the end of this resource page.

NBIM standards will merge data interoperability standards, content values and taxonomies, and process definitions to create standards which define "business views" of information needed to accomplish a particular set of functions as well as the information exchange standards between stakeholders. This is significantly different than previous initiatives which have focused primarily on data-centric approaches. Using business views as guides, NBIMS standards will identify information needed to support these views, appropriate content standards, and provide a technical description that developers can use to provide supporting computer-based applications.

To illustrate this and to give readers a sense of what to expect, here are some of the distinguishing characteristics of and goals for the Committee:

The scope and planned products are much more practice-oriented rather than data-centric. Both the organization of and representation on the Committee reflect this intent.

The Charter assumes and encourages participants from, and value propositions for, all phases of the building process lifecycle.

A primary goal is to maximize value for all process participants involved in the building lifecycle.

A primary strategy is to maximize existing research and development through alliances, cross-representation, active testing and prototyping, and an open and inclusive approach to both membership and results. NBIMS will, through

memorandums of understanding, recognize and harmonize its work with other standards-development organizations.

The Committee has significant representation from government owners, private and government practitioners, vendors, and specialist professionals. It is actively seeking more involvement from, for example, private owners, A/E/C practitioners, property and facility managers, and real property professionals.

The Committee supports the view that a building process lifecycle is not a strictly linear process but is a primarily cyclical process with feedback and cycle-to-cycle knowledge accumulation. The best representation of the building process lifecycle is therefore believed to be a business process helix with a central knowledge core and external nodes representing process suppliers and external consumers. Between these three elements exist information interchange "synapses" which require exchange rules

One of the principal products of the Committee's work will be process standards describing parties to a process and the contracted information exchange requirements between the parties. It has been estimated that about 250 process definitions will eventually be required to support an interoperable building supply chain. Through a spiral development process, NBIMS plans to release developments in packages that will be immediately useful even as each release adds additional and more mature concepts and practices. The first packages are scheduled to be available in late 2006.

NBIMS will support the development of content standards including taxonomy standards such as CSI OmniClass; which provides organized classification of elements important to the building process lifecycle.

NBIMS will recognize and facilitate the harmonization of software implementation views as they provide necessary "machine interpretable" data sources to the building information exchange process. buildingSMART™, .ifc, ifcXML, BLIS, AEX, CSI/2 and others are examples of software implementation views.

Vendors are actively participating on the Committee because they see value in having consistent and predictable processes to which they may apply their technical solutions. Having to develop, market and maintain products to support multiple, inconsistent processes, content, and interchange methods is expensive and complicates the product development cycle.

Though not a CAD standard, NBIMS will address CAD graphic and non-graphic information and processes as well as phases both before and after design and construction (where CAD is most often used). However, the National CAD Standard will continue to be important as, for the foreseeable future, building processes will continue to need standards for 2D drawings as well.

By now, readers should understand that the work of the National BIM Standards Committee is the next logical step in transforming the building supply chain. The Standard assumes that a paradigm change is required, since the definition of paradigm change is "reforming the underlying pattern or model on which actions are based". Participants in the building supply chain, through standards development and use of existing BIM technologies are already well on the way to changing the underlying patterns and operating practices used during the building lifecycle. But to realize the greatest efficiencies, BIM approaches must be based on broad aggregations of best practices rather than narrow, project-specific, proprietary solutions. By focusing now on the business view of contracted information exchanges and best-use of interoperable data sources, and by expanding the conceptual scope of BIM to include all phases of the building lifecycle, we can realize promised new levels of quality and efficiency.

APPLICATION

The application of BIM is pertinent to at least all the following participants in the facilities industry:

Owners—High level summary information about their facilities Planners—Existing information about physical site(s) and corporate program

needs Realtors—Information about a site or facility to support purchase or sale Appraisers—Information about the facility to support valuation Mortgage Bankers—Information about demographics, corporations, and

viability Designers—Planning and site information Engineers—Electronic model from which to import into design and analysis

software Cost & Quantity Estimators—Electronic model to obtain accurate quantities Specifiers—Intelligent objects from which to specify and link to later phases Contracts & Lawyers—More accurate legal descriptions as well as more

accurate to defend or on which to base litigation Construction Contractors—Intelligent objects for bidding and ordering and a

place to store gained information Sub-Contractors—Clearer communication and same support for contractors Fabricators—Can use intelligent model for numerical controls for fabrication Code Officials—Code checking software can process model faster & more

accurately Facility Managers—Provides product, warranty and maintenance information Maintenance & Sustainment—Easily identify products for repair parts or

replacement Renovation & Restoration—Minimizes unforeseen conditions and the resulting

cost Disposal & Recycling—Better knowledge of what is recycleable Scoping, Testing, Simulation—Electronically build facility and eliminate

conflicts Safety & Occupational Health—Knowledge of what materials are in use and

MSDS Environmental & NEPA—Improved information for environmental impact

analysis Plant Operations—3D visualization of processes Energy, LEED—Optimized energy analysis more easily accomplished allows for

more review of alternatives - impact of re-siteing by 5 degrees for example Space & Security—Intelligent objects in 3D provide better understanding of

vulnerabilities Network Managers—3D physical network plan is invaluable for troubleshooting CIO's—Basis for better business decisions and information about existing

infrastructure Risk Management—Better understanding of potential risks and how to avoid

on minimize Occupant Support—Visualization of facility for finding places - people can't

read floor plans First Responders—Minimize loss of life and property with timely and accurate

information

Each of the above requires information as well as creates information for others. The optimized BIM would only contain the information needed by others, however since this is currently an expanding concept it is likely better to err on the side of collecting too much information.

EMERGING ISSUES

This entire effort is an emerging issue and is the primary subject of nearly every forum and conference in the facility industry today. It stands to go down as one of the most notable disruptive business concepts in the industry since its inception, if implemented in its entirety. The development of the National BIM Standard will take years to complete and will evolve in a series of more detailed versions over time. The initial version will only touch on the overall scope of the issue and the associations and practitioners will collaborate to develop common languages and business processes to enhance each others activities over many years to come.

RELEVANT CODES AND STANDARDS

This section will be completed later as the National BIM Standard is currently under development and to get into detail prior to the consensus process would be inappropriate. Save it to say that at the current time the following items, listed alphabetically, are under consideration for inclusion in the National BIM Standard:

BIM Overall Scope, Coverage of Version 1.0 Business Processes & Business Rules CAD—National CAD Standard v 4.0 CAD-GIS-BIM Open Standard—OWS-4 Coast Guard Information Model Guidelines Construction Operations Building Information Exchange (COBIE) Project Code checking project Construction Scheduling SDEF mapping to IFC Contract Language for BIMs Data Models and Data Structures Ductwork fabrication ductXML mapping to IFC Structural Steel CIS/2 mapping to IFC Exchange Data Worksheet FIATECH Roadmap GSA BIM Guidelines Information Delivery Manual (IDM) Documentation BIM Capability Maturity Model NIST Project Handover Guide CSI OmniClass Tables OSCRE Taxonomies International Reference Standards

International Alliance for Interoperability, IFC's (ISO PAS 16739) STEP (ISO 10303) Integration of life-cycle data for process plants including oil and gas

production facilities (ISO 15926) Framework for Information (ISO 12006)

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INTRODUCTION

Architecture and Urban Planning are related endeavors that focus on different geographic scales. Architecture works at the scale of the individual building and immediate site, while planning works at the scale of neighborhoods, municipalities, and regions. In addition, planning has developed many specializations that focus on different aspects of the larger built environment, such as affordable housing, transportation,

economic development, protection of natural resources, land use planning, and community development.

Planning emerged from a need to overcome the disease, squalor, and poverty that were urban side effects of the industrial revolution. Planners therefore are concerned with a wide range of social, political, and economic factors beyond those that are the immediate concerns of building owners.

An important function of planning is to engage citizens in the process of developing a vision for how they want their community and its surrounding region to evolve over time, what attributes are important to protect, and where new development should be encouraged. The success of this process depends on listening, discovering shared values, and recognizing how the parts of a neighborhood, a city, or a region relate to one another and contribute to its overall vitality. Planners then work with a variety of partners in the public, private, and nonprofit sectors to craft policies, land use regulations, and incentives to help the community achieve its goals.

The Planner's Role in Whole Building Design

The architect, if designing from a whole building design perspective, will be looking simultaneously at inside functional aspects, and how they might relate to the site conditions such as sun/wind/view orientation. Architects, engineers, landscape architects, and other design professionals will work in conjunction with the planner to ensure that environmental, social, and economic issues directly affected by construction or redevelopment are looked at. These include the building's effect on the natural environment (increased impervious surface, runoff, elevated water tables, preservation of wetlands and natural species, etc.), on the economy (increased tax base, more jobs, costs of schools generated by houses, etc.), community infrastructure (cost and timing of road and utility systems, different modes of transportation, etc.) and, in general, on all factors that affect the quality of life or residents of the larger area within which the individual building is situated.

Different constituencies within any given community often have differing opinions about community goals. Hence, an important role of planners is to help manage the process by which decisions can be made that best balance these differences. Planners are trained in the use of a variety of engagement and consensus-building techniques, ranging from interactive websites and electronic town meetings to more traditional public meetings.

Increasingly, planners and other design professionals are using more collegial and collaborative techniques to help community groups reach consensus on development issues. One such technique is the "community charrette." A charrette is essentially a design workshop where designers, residents, developers, city officials, planners, and other interested parties come together to envision and plan an area as small as a building site or as large as a neighborhood. It is a short-term, intense design tool to flesh out a community's vision for the future.

In all regions of the United States and in all sizes and types of communities, when citizens come together to discuss their hopes for their community, they often express a desire that it be a place that is economically viable, environmentally sustainable, and socially equitable. As they explore ways to achieve these goals and identify impediments to that progress, concerned citizens often come face to face with the regional dynamics that promote sprawl, use up irreplaceable farmland and open space, and undermine long-standing community investments.

Planners can assist elected officials, civic leaders, and a variety of other stakeholders, understand these dynamics and examine the costs and benefits of different development and conservation options. At the same time, they can elucidate how adhering to the principles of the Smart Growth and New Urbanism movements and employing many of the techniques they espouse, can help communities achieve their economic, environmental, and equity goals. In this way "whole building design" can become part of a holistic approach to neighborhood, community, and regional design.

Sprawl and the Built Environment

Throughout America, urban sprawl has been a major contributor to the degradation of the environment, increased commuting times, destruction of viable farmland, and loss of community fabric and social cohesion. An average of 45.6 acres of U.S. farmland is developed every hour, much of it for housing. In 1950, the average size of a newly built home in the United States was 983 square feet. In 2000 that number increased to 2,265 square feet. The result of our building habits is that metropolitan land consumption is vastly outpacing population growth. For example, between 1970 and 1990, metropolitan Chicago's population increased by 4% while the land consumed for housing increased by 46%.

We can choose the way we grow. There are great social, economic, and environmental benefits to compact and sustainable design as an alternative to current sprawling development patterns. Often when cities try to stop sprawl, they encounter regulations adopted in the past that have been adverse to smart growth. Regulations such as minimum lot sizes, setbacks, and building footprints have had serious social consequences in communities.

Unfortunately compactness and increased density are still seen in many suburban areas as code words for mixing unequal economic or racial populations. Maintaining low density is still used as a device to keep up land development costs, increase values, and keep the "them" people out of an area. Smart growth is used as a tool for dismantling exclusionary regulatory barriers that prevent compact and sustainable growth from occurring and increasing environmental quality, economic development, and social equity.

Smart Growth

What is Smart Growth?

In contrast to conventional sprawling development practice, Smart Growth takes a regional approach to development and focuses a larger portion of growth in areas where development has already occurred. Smart Growth America defines smart growth as the outcome of six core values shared by the majority of Americans. Smart Growth communities promote:

Neighborhood Livability - Communities should be safe, affordable, attractive, and convenient. Smart planning can achieve all of these neighborhood goals, while sprawling communities can only achieve some.

Better Access and Less Traffic - This goal provides options for people and equal access for those without cars.

Thriving Cities, Suburbs, and Towns - Reusing and reinvesting in the communities that exist today is critical. Preservation and redevelopment of buildings can help improve existing neighborhoods.

Shared Benefits - Enable all sectors of society to benefit from economic prosperity.

Lower Costs, Lower Taxes - Building infrastructure for sprawl costs taxpayer money. Reinvesting in areas with existing infrastructure saves taxpayers money.

Keeping Open Space Open - Open space and natural features are community assets that are preserved through good planning and design. Developers can preserve these features through optimizing site developments.

The American Planning Association's Policy Guide on Smart Growth endorses these principles and guides its members to utilize smart growth principles in the planning process. APA also has a number of publications geared towards helping communities that want to revise state statutes and local ordinances to promote smart growth principles.

APA is a member of the Smart Growth Network, a coalition of government agencies and nonprofit organizations dedicated to advancing smart growth. Other agencies and organizations participating in the network include the State of Maryland, the U.S. Environmental Protection Agency, the National Association of Realtors, and the Local Initiatives Support Corporation.

Reinvestment in Our Cities

A key strategy for smart growth is reinvestment in our cities. Cities offer many opportunities and amenities that don't necessarily exist in outlying areas. These include:

Existing infrastructure Historic Character Access to public transportation, parks, schools, retail, and jobs Pedestrian friendly streets

Also, many urban areas have reinvestment opportunities in vacant parcels and existing buildings, and some municipalities offer tax credits for brownfield redevelopment.

New Urbanism

The "New Urbanism" movement complements smart growth in many respects. New Urbanist communities feature compact neighborhoods that offer residents transportation options, open space amenities, and retail and live/work opportunities. New Urbanism can be new development or it can be integrated into an existing urban context.

The Charter for New Urbanism highlights 27 principles necessary for achieving the objective of a new urbanist community. New Urbanist communities encourage:

1. Mixed land uses, building types, and densities to promote diversity. Buildings should respect local and regional character to promote a sense of place.

2. Infill and rehabilitation opportunities 3. Community design standards in order to allow a neighborhood to maintain its

local character to combat the "placelessness" associated with sprawl 4. Neighborhoods that promote walking and public transit 5. Neighborhood density coupled with regional preservation of farmland and

natural features

The health and character of a neighborhood are shaped by its diversity, walkability, and access to public transportation. Effective building design can support these objectives. A neighborhood with a wide range of housing options—with regard to cost, size, and style—can be inhabited by various demographic groups. For example, accessory housing and granny flats open a neighborhood to the elderly and others living on a small, fixed

income. Walkability and access to a variety of modes of transportation makes a neighborhood accessible for more people, including people with disabilities and those who can not afford, or choose not to own a car.

Complementary Approaches

In striving to create healthier communities, planners and designers draw upon a variety of techniques including the following:

Historic Preservation—Cities may designate certain sections as "historic districts" and require adherence to special design guidelines so that the historic character of existing or renovated buildings is respected and new construction is compatible. Historic preservation functions such as designation, design review, and technical assistance may be housed in a separate public agency, but are often part of the planning department. Historic preservation enhances the aesthetic character of a neighborhood and can generate economic development in areas where tourism is a driving force in the local economy. This is particularly true in older commercial downtown areas that are unable to compete head-to-head with suburban, commercial strip development. The older districts have to transform themselves and attract a tourist or day-trip oriented customer with antique shops, restaurants, art shops, museums, entertainment, or other unique activities. (See also WBDG Historic Preservation.)

Transit Oriented Development (TOD)—TODs and other forms of development (transit corridors, station area zones, and transit districts) are high density, mixed-use and walkable areas built around transit nodes. TOD zones promote the use of many means of transportation. Special development zones are often created within a quarter mile radius of the transit stop, considered a comfortable walking distance for pedestrians.

The Federal Transit Authority has created the Transportation Planning Capacity Building Program, which serves as a clearinghouse for technical assistance and best case practices on effective transportation planning initiatives.

Building Design—Some jurisdictions now have urban design standards incorporated into their zoning codes. Elements such as window size, building materials, and lighting can be reviewed by a city to ensure that it is consistent with community character, promotes safety and security, and integrates the public and private realm.

An example of a town that has building design review is Apex, North Carolina. The town has done several things to ensure that Apex maintains its small town, walkable character. They have set up a Traditional Neighborhood Design (TND) district to promote higher density, walkable neighborhoods. Apex has required design review for all commercial and industrial uses within town limits, as well as for all residential development within the TND and other designated districts. Building design within Apex must be compatible with the architecture of the town and is achieved through techniques such as the repetition of roof lines, the use of similar proportions in building mass and outdoor spaces, similar relationships to the street, similar window and door patterns, and the use of building materials that have color, shades, and textures similar to those existing in the immediate area of the proposed development.

Street Elements

The aesthetic and social quality of neighborhoods can be improved through the layout of the streets and the streetscape elements that are provided.

Street Widths: Short blocks with narrow streets support walking, calm traffic speeds, and promote more neighborhood cohesion. Streets should complement the uses that are found on them. Neighborhoods with many pedestrians, bicyclists, and street activity, for example, should have slow moving cars.

Sidewalks: Sidewalks were once an installation that was taken for granted in neighborhood design. In some municipalities, sidewalks are not a necessity and are often eliminated in subdivision design. The result has been complete auto-dependency.

Planners value sidewalks because they: Provide pedestrian safety - According to The National Highway Traffic Safety

Administration, in 2001 there were 78,000 pedestrians injured and 4,882 pedestrians killed by cars in the United States.

Support a healthy lifestyle by promoting physical activity - Walkability is increasingly important as obesity has reached epidemic proportions. Almost 59 million individuals in the United States are considered obese.

Promote social gathering - Wide sidewalks allow for benches, outdoor seating for restaurants, and activities that bring people together.

Lighting: Good lighting provides visibility along with a greater perception of safety. Streetlights can be at a pedestrian or auto-oriented scale. Lighting fixtures can reflect the aesthetic character of a neighborhood, particularly in historic neighborhoods.

Street Trees: Trees act as a buffer between pedestrians and automobiles. They provide shade in the summertime and are an aesthetically pleasing addition to any streetscape.

Parking: On-street parking slows speeds of through-traffic and provides a buffer between pedestrians and moving vehicles. Metered spaces generate revenue for cities while reducing the need for additional off-street parking sites.

When combined, these elements convey an image of a neighborhood in which residents and building owners take pride. Both of the neighborhoods depicted here are in urban areas with a mix of retail and residential along the corridor. Which one of these neighborhoods would you rather live in?

Emerging Techniques in Planning

When cities and regions take the initiative to stop sprawling and embrace smart growth values, they often run into regulatory barriers to changing the physical landscape created by traditional zoning. As part of their larger efforts to help communities achieve the social, economic, and environmental goals of smart growth, planners and other design professionals have crafted several alternatives to traditional zoning in an effort to achieve more control over building and site design.

Among these alternatives are various "form-based development codes," which emphasize the design character of the area and allow greater flexibility in the range of land uses. Three types of form based development codes have emerged.

Form Based Coding—Form based coding is a regulatory approach designed to shape the physical form of development while setting only broad parameters for use. They are created through community participation and visioning that reflects the community character of a locality. Many cities are experimenting with form-based by adopting them for specific neighborhoods and districts.

Form District Zoning—Form District zoning incorporates a two-tiered approach combining the use regulations of existing zoning districts with form districts that regulate density and intensity and prescribe contextual design standards such as build-to lines based upon the established development pattern.

Smart Code —Smart codes are based upon the New Urbanist concept of transect planning. The smart code sets up different "ecozones" on a continuum from rural to urban. These zones range in scale and intensity from T-1 (the natural zone) to T-6 (The Urban Core). Each transect has a different set of rules for building height, setbacks, street design, etc.

Enlarging the Collaborative Process

Using the techniques described above, planners can help communities achieve many of their social, environmental, and economic goals. However other elements of a successful community such as civic participation, affordable housing, environmental justice, and ethnic and economic diversity cannot be achieved through physical design alone. Planners and design professionals must work with a diverse group of stakeholders and disciplines to ensure that these issues are addressed in a holistic manner.

MAJOR RESOURCES

The Congress for New Urbanism—The 27 principles that guide policy to make a city more livable on a regional, neighborhood, and building scale

Land Use Law Center—Pace University Land Use Law CenterNational Highway Traffic Safety Administration—National Traffic Safety FactsOvercoming Obstacles to Smart Growth through Code Reform—Local Government

CommissionPathways in American Planning History—A Thematic Chronology, by Albert Guttenberg,

FAICPPhysical Activity and Good Nutrition: Essential Elements to Prevent Chronic Diseases and

Obesity—National Center for Chronic Disease Prevention and Health PromotionPolicy Guide on Planning for Sustainability—American Planning Association Policy Guide on Smart Growth—American Planning AssociationSmart Growth America—What is Smart Growth?Unified Development Ordinance—City of Apex, NC

Organizations/Associations

American Planning AssociationCongress for New UrbanismFederal Transit AdministrationLocal Government CommissionSmart Growth America