Sustainable Sites

Heat Island Effect

Intent:

Reduce heat islands (thermal gradient differences between developed and undeveloped areas) to minimize impact on microclimate and human and wildlife habitat

Natural Resources Canada

Heat Island Effect

When this thermal image was taken, air temperatures were 80 degrees but surface temperatures reached 118 degrees

Thermal Image of Atlanta, NASA Earth Observatory Web Page

Question

Problems associated with heat island effect include:

• Human health and comfort

• Increased energy needs for cooling

– The heat island effect is estimated to cost L.A. about $100 million per year in energy costs1

• Microclimate changes such as rainfall patterns

– Monthly rainfall is about 28% greater between 20-40 miles downwind of cities, compared with upwind.2

1. eetd.lbl.gov/HeatIsland/EnergyUse/ 2. Fuchs, Dale (2005-06-28). The Guardian.

Heat Island EffectNon-Roof

Potential Technologies & Strategies:

Provide a combination of the following strategies for the site hardscape:

• Shade within 5 years of occupancy

• Light-colored paving (with a solar reflective index [SRI] of at least 29)

• Open grid pavement systems

Heat Island EffectNon-Roof

Potential Technologies & Strategies:

• Place parking spaces under cover (defined as underground, under deck, under roof, or under a building). Any roof used to shade or cover parking must have an SRI of at least 29.

Automated Munich under-street parking, www.roadtraffic-technology.com

Tips from the Pros

Definitions:Solar Reflectance/Albedo – The ratio of reflected solar energy to the incoming solar energy. A reflectance of 100% means that all of the energy striking a reflecting surface is reflected back into the atmosphere, and none of the energy is absorbed by the surface.SRI – The measure of a material’s ability to reject heat. It is calculated based on both emissivity and reflectance values. Black has a value of 0, and white has a value of 100, meaning that the lighter the color of the material, the higher the SRI.

Tips from the Pros

Definitions:Emissivity – the ability of a material to emit heat by radiation.Reflectance – the fraction of incident radiation reflected by a material.

Potential Technologies & Strategies:

• Use roofing materials that have a high Solar Reflective Index (SRI) value.

• Install a vegetated (green)roof.

Heat Island Effect - Roof

Roof Type Slope SRI

Low-Sloped Roof <2:12 78

Steep-Sloped Roof >2:12 29

Green Roof: Manulife Building BostonSasaki Associates

White TPO & metal roofs

Light Pollution Reduction

Light Pollution Reduction

Intent:Eliminate light trespass from the building and site, improve night sky access and reduce development impact on nocturnal environments.

Light Pollution Reduction

Potential Technologies & Strategies:For Interior Lighting Make sure the interior lighting is not exiting out the windows.

OR

Automatically control all non-emergency interior lighting to turn off during non-business hours. (Provide manual override capability for after hours use.)

Light Pollution Reduction

ANDFor Exterior Lighting Only light areas for safety and comfort. Do not exceed the lighting power densities for exterior areas as defined in ASHRAE/IESNA Standards 90.1-2007.

Light Pollution Reduction

The exterior lighting requirements include fixture cut-off requirements.

Light Pollution Reduction

The exterior lighting requirements also include footcandle limits for the site boundary. 0.1

Light Pollution Reduction

The specific requirements vary by project zone:• LZ1 – Dark (Park and Rural Settings)• LZ2 – Low (Residential Areas)• LZ3 – Medium (Commercial/Industrial, High-Density

Residential)• LZ4 – High (Major City Centers, Entertainment

Districts)

Tenant Design & Construction Guidelines (LEED-CS Only)

Intent:

To educate tenants about implementing sustainable design & construction for their tenant fit-out.

Requirements:

Provide a document, communicating:

• What’s green about the Core & Shell project and what are the project’s sustainability goals.

• Overview of LEED CI and how the attributes of the Core & Shell building may contribute to achievement of CI certification.

Tenant Design & Construction Guidelines (LEED-CS Only)

• Information that enables the tenant to coordinate their design, construction and potential LEED certification with the Core & Shell systems.

• Recommended strategies, products, materials and services.

Tenant Design & Construction Guidelines (LEED-CS Only)

How can a LEED CS certified building help a CI project achieve certification?• Site Selection: Select a LEED Certified Building (5

points)• Optimize Energy Performance (daylighting & HVAC)• Measurement & Verification (submetering)• Tenant Space, Long Term Commitment (10 year

min.)• Environmental Tobacco Smoke Control (no smoking)

Tenant Design & Construction Guidelines (LEED-CS Only)

How can a LEED CS Certified Building help a CI project achieve Certification?• Outdoor Air Delivery Monitoring (CO2 sensors/flow

meters)• Increased Ventilation (HVAC capacity)• Controllability of Systems, Thermal Comfort (HVAC

type)• Daylight & Views (narrow floor-plate, windows, open

plan)• Innovation & Design (green housekeeping,

education, etc.)

Environmental Site Assessment (LEED-Schools Only)

Intent:

To ensure that the site is assessed for environmental contamination and if contaminated, that the environmental contamination has been remediated to protect children’s health.

Strategies:

• Conduct a Phase 1 Environmental Site Assessment to determine if environmental contamination exists at site.

• If contamination is suspected conduct a Phase 2 Environmental Site Assessment.

School sites contaminated by past use as a landfill are

ineligible for LEED certification.

Joint Use of Facilities (LEED-Schools Only)

Intent:

To make the school a more integrated part of the community by enabling the building and its playing fields to be used for non-school events and functions.

Strategies:

• Share use of auditorium, gymnasium, cafeteria, classrooms, playing fields, and/or parking.

• Provide space to the community for a commercial office, health clinic, community service center, police office, library, media center, parking lot, and/or a commercial business.

• Provide student access to non-school resources, similar to those listed under the first bullet above.

SS C1 LEED Certified Design and Construction 4

SS C2 Building Exterior and Hardscape Management Plan

1

SS C 3 Integrated Pest Management, Erosion Control and Landscape Management Plan

1

SS C 4 Alternative Commuting Transportation 3-15

SS C 5 Site Development 1

SS C 6 Stormwater Quantity Control 1

SS C 7.1-7.2 Heat Island Reduction 2

SS C 8 Light Pollution Reduction 1

LEED Credits – Sustainable SitesExisting Buildings Operations &MaintenanceNo Prerequisite, 26 points

Requirements:Show that the building has previously been LEED certified, either under LEED for New Construction, OR under LEED for Core & Shell in combination with >75% under LEED for Commercial Interiors.

LEED EBOMLEED Certified Design & Construction

Intent:Employ an environmentally sensitive, low-impact building exterior and hardscape management plan that helps preserve surrounding ecological integrity.

LEED EBOM

Bldg Exterior and Hardscape Management Plan

LEED EBOMBldg Exterior and Hardscape Management Plan

Requirements:The plan must address all of the following operational elements that occur on the building and grounds, as applicable:

• maintenance equipment • snow and ice removal • cleaning of building exterior • paints and sealants used on building exterior• cleaning of sidewalks, pavement and other hardscape

LEED EBOMBldg Exterior and Hardscape Management Plan

Strategies:• Encourage manual snow removal• Employ ENERGY STAR and electric maintenance

equipment • Target exterior cleaning• Require Green Seal certified exterior building

cleaning products• Require the use of environmentally benign salts for

de-icing• Require proper maintenance of sidewalks for

pedestrians• Require lower toxicity sealants and caulk for

exterior applications• Train personnel accordingly

LEED EBOMIntegrated Pest Management, Erosion Control & Landscape Management Plan

Intent:

Perform pest control, erosion control, and landscape management in an environmentally sensitive manner.

LEED EBOMIntegrated Pest Management, Erosion Control and Landscape Management Plan

Strategies:

• Select native and adaptive species• Apply pesticides only when needed• Employ natural pest control measures• Reduce erosion from the site by employing silt fences and retention ponds• Require proper training for maintenance personnel • Require feedback loops such that progress can be gauged• Reduce water needed for vegetation irrigation

LEED EBOMAlternative Commuting Transportation

Intent:

Reduce commuting via single-occupant, conventionally fueled vehicles.

Strategies:

• Telecommuting• Compressed workweeks• Mass transit• Walking

• Carpools• Vanpools• Low-emitting or fuel-efficient or alternative-fuel vehicles.• Bicycles

LEED EBOMReduced Site Disturbance

Requirements:

Have in place native or adaptive vegetation covering a minimum of 25% of the site area, excluding the building footprint.

Improving and/or maintaining off-site areas with native or adapted plants can contribute to this credit. Every 2 square feet off-site can be counted as 1 square foot on-site.

LEED EBOMReduced Site Disturbance

Strategies:

• Create a master site plan.

• Remove excess and unnecessary paver materials and hardscape.

• Replace with native and adaptive species.

Intent:To reduce the amount of runoff & increase infiltration.

LEED EBOMStormwater Management

Requirements:Implement a stormwater management plan that requires the infiltration, collection and reuse of runoff or increases evapotranspiration(the sum of evaporation and plant transpiration from the Earth's land surface to the atmosphere).

Remember that there are synergies between stormwater management, energy reduction, and the heat island effect. By installing a green roof, the project team will increases its chances of achieving credits in multiple categories.

Tips from the Pros

Solaire project. Battery Park City, New York. Photo by birdw0rks

LEEDMHeat Island Effect: Non-Roof

Very Similar to

LEED-NC Credits

Requirements:

White roofs can become dirty and lose their ability to reflect the sun’s heat. Cleaning all SRI compliant roofing helps to maintain its performance.

LEED EBOMHeat Island Effect: Roof

LEED EBOMLight Pollution Reduction

Strategies:

Since the building is existing, one option for O&M is to measure the night illumination levels at regularly spaced points around the perimeter of the property, taking the measurements with the building’s exterior and site lights both on and off. Illumination levels with the lights on must be less than 20% above the levels with the lights off.

www.utahskies.org/lightpollution

Questions