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NCDOI OSFM Evaluation Services Scope of DOI White Paper: The Purpose of this document is to provide clarification on North Carolina State Code requirements to Code Officials (CEO), who are agents for the Authority Having Jurisdiction (AHJ). DOI File #: WP-009-11 Edition Date: May 10, 2011

Subject of White Paper: Code Considerations for Constructing a Covered Outdoor Space Adjacent to an Existing Restaurant, Bar or Nightclub

1.0 Table of Contents ………………………………………………….…………………………….. 1 2.0 Intent ........................................... ………………………………………………………………... 2

3.0 Code References ................................................................................................................ 2

4.0 Code Definitions ............................................................................................................... 3

5.0 Code Considerations ....................................................................................................... 4

A. Occupancy Classifications of the Existing Building and the Covered Addition …… . 5

B. Occupant Load of the Existing Building and the Covered Addition …………………. . 6

C. Construction Type of the Existing Building and the Covered Addition …………….. .. 8

D. Area and Height of the Existing Building and the Covered Addition ………………….. 9

E. Determine if a Building Qualifies as“"Non-Separated” or “Separated” Occupancies in a Mixed Occupancy Multiple Tenant Building ………………………………….. 11

F. Maintaining Means of Egress for the Existing Building during Construction of the Covered Addition ……………………………………………………………………… 13

G. Fire Suppressions Systems for the Existing Building and the Covered Addition ……………………………………………………………………………………… ....... 13

H. Plumbing Fixtures for the Existing Building and the Addition of an Uncovered Outdoor Area or a Covered Addition ……………………………………………….. 14

I. Energy Requirements for the Covered Addition ……………………………………… .. 15

J. Structural Requirements for the Covered Addition ……………………………………… 15

K. Guards at the Covered Addition ……………………………………………………..…… 16

L. Pliable Light Transmitting or Fabric Curtain System for Weather Protection at the Covered Addition ……………………………………………………………………… 16

M. Accessibility Requirements for the Covered Addition ………………………………… . 16

6.0 References ....................................................................................................................... 17

7.0 Photo Resources ............................................................................................................. 17

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2.0 INTENT

This Document addresses 2009 North Carolina State Building Codes (NCSBC) consideration where a permanent or a temporary roof structure will be constructed over an outdoor space (for example, a patio, deck, balcony, etc.) that is adjacent and physically attached to an existing building. The commercial establishment in the existing building is primarily intended for the consumption of food and/or alcoholic beverages (restaurant, bar or nightclub) and the new covered outdoor space will serve the same function. The structural framing over the outdoor space may support a solid covering (i.e., metal, shingles, fabrics, light transmitting plastic roof panels, etc.) or a semi-solid covering (i.e., structural framing only or supporting lattice work, grating, etc.). (Figures 1, 2 & 3). These establishment types include, but are not

limited to, banquet halls, night clubs, restaurants or taverns and bars and are usually classified by occupancy in the NCBC as either a Business (Group B) or an Assembly (Group A-2), depending on their calculated aggregate design occupant load. The establishment may be located in a single occupancy use building or may be a tenant space in a multi-tenant building with

multiple non-separated or separated occupancy uses. This document assumes that the new covered outdoor space is located on the level of exit discharge and is not separated from the existing building by a fire wall (NCBC-705). This document is not applicable to awnings and canopies as addressed in 3105 of the North Carolina Building (NCBC).

3.0 CODE REFERENCES*

A. North Carolina Building Code (NCBC)

B. North Carolina Fire Code (NCFC)

C. North Carolina Energy Code (NCEC)

D. North Carolina Plumbing Code (NCPC) * Unless specifically noted otherwise, all code references are the 2009 edition.

Figure 2- Plastic enclosure supported by

steel frame.

Figure 1-Retractable light transmitting fiberglass

enclosure supported by aluminum frame.

Figure 3 – Wood lattice supported by wood frame.

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4.0 CODE DEFINITIONS

Assembly Group A-2 Occupancies (NCBC-Section 303): Assembly uses intended for food and/or drink consumption including, but not limited to (1) banquet halls, (2) night clubs, (3) restaurants and (4) taverns and bars. Note that Exception # 1 under Section 303.1 states “A building or tenant space used for assembly purposes with an occupant load of less than 50 persons shall be classified as a Group B occupancy.” (See 5.0-A of this document for additional information on occupancy classification and 5.0-B on calculating the design occupant load).

Business Group B Occupancies (NCBC-Section 304): Business Group B occupancies includes,

among others, the use of a building or structure, or a portion thereof, for office, professional or service-type transactions, including storage of records and accounts. NCBC-304.1 lists examples of business occupancies.

AREA, BUILDING (NCBC-Section 502): The area included within surrounding exterior walls (or

exterior walls and fire walls) exclusive of vent shafts and courts. Areas of the building not provided with surrounding walls shall be included in the building area if such areas are included within the horizontal projection of the roof or floor above.

FIRE SEPARATION DISTANCE (NCBC-Section 702): The distance measured perpendicular

from the building face to one of the following: 1. the closest interior lot line; 2. to the centerline of a street, an alley or public way; or 3. to an imaginary line between two buildings on the property. The distance shall be measured at right angles from the face of the wall. Refer to NCBC-Table 602.

FIRE AREA (NCBC-Section 702): The aggregate floor area enclosed and bounded by fire walls,

fire barriers, exterior walls or fire-resistance-rated horizontal assemblies of a building.

FIRE BARRIER (NCBC-Section 702): A fire-resistant-rated wall assembly of materials designed

to restrict the spread of fire in which continuity is maintained. (Fire barrier requirements are addressed in NCBC-Section 706). Note that a fire barrier provides a higher degree of protection than a fire partition (NCBC-708), but lacks the inherent structural integrity of a fire wall. Fire barrier assemblies must be continuous from the top of a fire-resistance-rated floor/ceiling assembly to the underside of the floor or roof slab or deck above. The barrier must be constructed tight and securely attached to the underside of the floor slab or roof deck.

FIRE PARTITION (NCBC-Section 702): A vertical assembly of materials designed to restrict the

spread of fire in which openings are protected. (Fire partitions are addressed in NCBC-Section 708).

FIRE WALL (NCBC-Section 702): A fire-resistant-rated wall having protected openings, which

resist the spread of fire and extends continuously from the foundation to or through the roof, with sufficient structural stability under fire conditions to allow collapse of construction on either side without collapse of the wall. (Fire walls are addressed in NCBC-Section 705).

FLOOR AREA, GROSS (NCBC-Section 1002): The floor area within the inside perimeter of the

exterior walls of the building under consideration, exclusive of vent shafts and courts, without deduction for corridors, stairways, closets, the thickness of interior walls, columns or other features. The floor area of a building, or portion thereof, not provided with surrounding exterior walls shall be the usable area under the horizontal projection of the roof or floor above. The gross floor area shall not include shafts with no openings or interior courts.

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Figure 4-After the construction of a covered outdoor space (beyond), existing exit(s) shall continue to be

code compliant.

FLOOR AREA, NET (NCBC-Section 1002): The actual occupied area not including unoccupied accessory areas such as corridors, stairways, toilet rooms, mechanical rooms and closets.

HORIZONTAL ASSEMBLY (NCBC-Section 702): A fire-resistant-rated floor or roof assembly of

materials designed to restrict the spread of fire in which continuity is maintained. (Horizontal assemblies are addressed in NCBC-Section 711).

5.0 CODE CONSIDERATIONS

For purposes of this document, it is assumed that the existing building complied with NCSBC in effect at the time the structure was permitted by the Authority Having Jurisdiction (AHJ). However, the CEO needs to confirm that any elements of the existing building, which may be affected by the addition of a covered outdoor space, will continue to comply with code. These elements include consistent construction type, exiting or other items that may also have been altered after the original Certificate of Occupancy was issued for the existing building. For these reasons, it is recommended that an Appendix B (Building Code Summary for All Commercial Buildings), with information on the existing building, be included as a part of the submittal for the proposed covered outdoor space. (Figure 4). As a resource, hard copies of former North Carolina Code editions are available for use at the DOI-OSFM Engineering Office, located on the second floor at 322 Chapanoke Road, Raleigh, NC 27603. Some former Codes can also be found on the DOI-OSFM web site under “STATE BUILDING CODES” at the following link:

http://www.ncdoi.com/OSFM/Engineering/engineering_home.asp

Note to Fire Inspectors - It is not uncommon for a covered outdoor space addition to have been constructed without a required permit or altered after the original Certificate of Occupancy was issued. It is incumbent upon the Fire Inspector to not assume that the type of construction and means of egress condition(s), etc. are code compliant. (Figure 5). The CEO’s review of the submittal requires basic project information for both the existing building as well as the addition of the proposed covered outdoor space. The following information should be addressed on Appendix B and included as a part of the submittal package:

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A. Occupancy Classification of the Existing Building and the Covered Addition

Determining the occupancy classification, or classifications, of an existing building and the proposed addition is essential to the correct application of subsequent requirements found throughout the North Carolina State Building Codes. Use and Occupancy Classifications are addressed in Chapter 3 of the NCBC. Section 5.0-B of this document addresses calculating the design occupant load.

1. Single use building has one occupancy group classification. For the purpose of this White Paper, a restaurant or bar is classified by use as either Assembly-Group A-2 or Business-Group B, based on the calculated design occupant load. An existing restaurant and/or bar (including a covered outdoor addition), with a calculated design occupant load more than 50 persons, is classified by occupancy use as Assembly-Group A-2. An existing restaurant and/or bar (including a covered outdoor addition), with a calculated design occupant load less than 50 persons, is classified by occupancy use as Business-Group B (Exception # 1 under NCBC-303.1).

2. Multiple tenant building may

have one occupancy classification (all office tenants, for example) or may have more than one occupancy group use and is identified by the NCBC as “mixed occupancy”, per NCBC-Section 508. (Figure 6).

Example of several occupancy groups that could be found in a multi-tenant (mixed occupancy) building could be a law firm or barber shop, etc. (classified as

Figure 5- All components of means of egress shall be code compliant. Table & chairs under the covered outdoor space shall not interfere with the path of exit access from the exit

of the building in the background.

Figure 6- Example of a multiple tenant building.

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Business-Group B), grocery store or drug store (classified as Mercantile-Group M). A restaurant/bar (which can be classified as either Assembly-Group A-2 or Business-Group B, depending on the calculated design occupant load and/or other factors).

3. Design options for addressing mixed occupancy in a building are as follows:

Option # 1- Non-separated uses, where the height, area and sprinkler requirements for the most restrictive occupancy are applied to the entire building (see NCBC-Section 508.3.2 and subparagraph 5.0-E.1 of this document);

or Option # 2 - Separated uses, where individual occupancies are separated by

rated fire barriers and compliance with area limitations is determined by (1) a unit formula, (2) no occupancy may occur on a floor higher than the limitation for the individual occupancy and (3) sprinkler requirements are limited to the fire area in which the occupancy occurs (see NCBC-Section 508.3.3 and subparagraph 5.0-E.2 of this document);

or

Option # 3 - Combination of non-separated and separated uses (see subparagraph 5.0-E.1 and 5.0-E.2 of this document);

or

Option # 4 - Separation of one or all of the occupancies with a fire wall which will create separate buildings (see NCBC-Section 705).

NOTE: Each design option, when the NCBC is applied correctly, should provide a building with an acceptable level of safety. The owner or his designer, not the CEO, is responsible for determining which option to use and this is required to be noted on Appendix B of the drawings. It is the responsibility of the CEO to confirm that the selected option is designed in a code compliant manner.

B. Occupant Load of the Existing Building and the Covered Addition The addition of a covered outdoor space to an existing restaurant, bar and/or nightclub usually increases the design occupant load of the entire establishment. 1. Considerations: The purpose for calculating the design occupant load is to

establish the maximum number of persons who occupy a building or a space at any one time. The maximum square feet per person is based on the use (NCBC-Chapter 3) of each space or room in accordance with NCBC-Table 1004.1.1, and not the occupancy classification of the building.

Example: Although a restaurant with an aggregate design occupant load of less than 50 persons is classified by occupancy as Group B (Exception #1 under NCBC-Section 303.1) for purposes other than code exiting requirements, this does not mean that the load is calculated at 100 sq. ft. gross per person as would be allowed for a Business use in NCBC Table 1004.1.1. Each space in a restaurant or bar is calculated as to the function. The dance floor, waiting area and bar will be calculated at 7 sq. ft. net/person (Assembly concentrated without fixed seats). The seating/dining area will be calculated at 15 sq. ft. net/person (Assembly un-concentrated). Other spaces will be calculated per person by use in the same manner, i.e., the kitchen at 200 sq. ft. gross/person,

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the storage room(s) at 300 sq. ft. gross/person, the office(s) and toilets at 100 sq. ft. gross/person, etc. Once each space is calculated individually, the load for all spaces is added together to become the aggregate design occupant load for the entire restaurant or bar. If the load equals or exceeds 50 persons, the restaurant or bar will be classified as Assembly Occupancy for all code purposes.

2. Importance of correct occupant load calculations: The calculated design

occupant load determines whether an establishment (restaurant, bar, etc.), primarily in the business of serving food and /or alcoholic drinks for consumption on the premises, is classified by occupancy as Group B or Group A in Chapter 3 of the NCBC. (Figure 7). An increase in the design occupant load could also trigger additional means of egress elements and/or fire protection systems. Under current code, the load threshold for occupancy classification as Business verses Assembly for a restaurant may have changed from a previous code:

a. For instance, the 1994 Building Code (with 1996/1997/1998/1999

Amendments), per Section 304.2.2, defined an establishment such as restaurant/bar/night club (used for assembly purposes) with less than 100 occupants to be classified by occupancy as Group B. Group A occupancy was defined as having 100 or more occupants.

b. Per Section 303.1-

Exception # 1 of the 2009 NCBC code, an establishment such a restaurant/bar/night club (used for assembly purposes) with less than 50 occupants in a building or a tenant space (in a multi-tenant building) can be classified as Business-Group B. With 50 or more persons, it is classified by occupancy as Assembly-Group A-2.

Example: A restaurant with an occupant load of 60 persons would have

been allowed under the 1994 NCBC as Business (Group B), since it had a calculated design load of less than 100 occupants. With the addition of a covered outdoor area having a calculated design load of 30 persons, the aggregate occupancy design load is now 90 persons. Although the establishment, under the 1994 NCBC, would have continued to be classified as Business occupancy, current code now requires that it now be classified as Assembly (Group A-2) because it has more than 50 occupants.

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3. Uncovered outdoor area: The construction of an uncovered outdoor area (patio, deck, porch, balcony, etc.) directly adjacent to an existing building or tenant space may not increase the occupant load of the existing building for the purpose of calculating means of egress, even when the intended use of the outdoor area is to serve the same function as the existing establishment.

Exception: When the means of egress from the uncovered outdoor area does not discharge directly to the public way by Code compliant means and the occupants are thus required to return into, and egress through, the adjacent existing building to reach a code compliant exit. In this scenario, the design occupancy load of the uncovered outdoor area is now added to the design occupancy load of the existing establishment for compliance with means of egress requirements as addressed in the NCBC-Section 1004.8. Calculating the occupant load, based on the type of use for both spaces, is required to be in accordance with current code requirements.

C. Construction Type of the Existing Building and the Covered Addition Correct classification of a building by construction type is essential for determining code compliance with respect to its occupancy classification. Type of construction also relates to the contribution of the structure itself to fuel load, the potential for spread of fire to adjacent structures and the effort required by the fire department to fight the fire. In accordance with Chapter 6 of the NCBC, it is necessary to know the construction type of the proposed covered outdoor space and the construction type of the existing building, particularly if they are not classified as the same type of construction (Figure 8). The following are considerations when reviewing for the correct construction classification:

1. Type of Construction: Each structure must be assigned one of five possible construction classifications-Type l, ll, lll, lV or V and as follows:

a. NCBC Table 601: Structural

members may be required to have a fire-resistance rating in accordance with NCBC-Table 601 (Fire-Resistive Rating Requirements for Building Elements).

b. NCBC Table 602: Exterior wall construction of the structure must satisfy the requirements in Table 602 (Fire-Resistive Rating Requirements for Exterior Walls Based on Fire Separation Distance).

Figure 8. The construction type of the proposed covered outdoor space and the construction type of the existing building

should be confirmed

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2. Existing and Addition Same Construction Type: If the covered outdoor space and the existing building are the same construction and fire-resistance (or non-fire-resistance) rating type, then the project will be reviewed as that type of construction for compliance under NCBC-Tables 503, 601 and 602.

3. Different Construction Types: Where two (or more) types of construction, even if separated by a fire barrier but not separated by a fire wall, occur in the same building, the most restrictive construction type shall determine the construction classification type of the entire building and shall not exceed any of the component limitations in NCBC-Table 503 and Table 602.

Example: If an existing building, classified as A-2 occupancy, is Type ll-B construction and the proposed covered outdoor space is to be Type V-B construction, then the existing building shall be re-classified as Type V-B construction.

4. It is recommended that a site plan shall be submitted for review of the following:

a. Compliance with NCBC-Table 602. (Refer to code definition of Fire Separation Distance under 4.0 of this document). Note-If the separation distance between the existing building (with the proposed covered outdoor addition) and any adjacent existing building(s) on the same property is less than 60 feet apart from the proposed covered outdoor addition, the construction and occupancy classification of the adjacent building(s) is to be provided.

b. Confirmation that the dedicated fire apparatus access, as required in the 2009 NC Fire Code-Section 503, will continue to be maintained after construction of the proposed covered outdoor space.

D. Area and Height of the Existing Building and the Covered Addition The provisions for governing the height and area of the building on the basis of occupancy group classification and type of construction are established in NCBC-Section 503. This Section also establishes NCBC-Table 503 as the primary tool for determining the minimum type of construction. NCBC-Table 601 is used with NCBC-Table 503 to determine acceptable risk and safety levels of a building and the materials used to construct it in relationship to fire hazard. In accordance with the descriptions in Chapter 3, classification by occupancy can be considered as establishing the level of “risk” associated with the occupancy use of a building. Use of the building is an indication of fire loading. The various construction types, described in Chapter 6 and Table 601 of the NCBC, can be thought of as reflecting various levels of safety provided by fire resistance. NCBC-Table 503 becomes a risk/safety matrix that sets a minimum level of safety (construction type) in accordance with the risk (occupancy classification reflecting internal fire loading). Refer to footnote “a” for general exceptions when reviewing NCBC-Table 503.

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1. Contribution of an Un-covered Outdoor Area (Patio, Deck, Balcony, etc.) to Building Area: None

2. Contribution of Covered Outdoor Area to Building Area (Refer to the code definition of Area, Building under 4.0 of this document):

a. When a permanent or

temporary roof structure is constructed over an outdoor area that is adjacent and is physically attached to an existing building, the square foot area under the covered outdoor space is to be added to, and included in, the square footage of the existing building to calculate the revised aggregate building area. (Figure 9)

b. When a permanent or temporary roof structure is constructed over an

outdoor area that is adjacent and is physically attached to a tenant space in a multi-tenant building where the other tenant spaces in the remaining building are non-separated per NCBC Section 706 and 711, the area under the covered outdoor space is to be added to, and included in, the square footage of all tenant spaces to calculate the aggregate building area. (See Section E-1 of this document).

3. Aggregate Area, Stories or Height Exceeds NCBC Table 503: Based on the construction type, if the existing building with the proposed outdoor covered space exceeds any of the limitations in NCBC-Table 503, the addition is not allowed by the NCBC without triggering further life safety components. Some examples of possible life safety components are as following:

a. An NFPA 13 sprinkler system, as addressed in NCBC-Section 506.3, can be provided to increase the allowable area (or height). The system must be installed throughout the entire building, which includes the existing building and the covered outdoor space. If the existing building is a multi-tenant building with multiple non-separate tenant spaces, a sprinkler system is required in all other non-separated tenant spaces.

b. Fire Wall (refer to the code definition of Fire Wall under 4.0 of this

document): Construction of a fire wall* divides a single building into separate buildings, as addressed in NCBC-705. The result is that all provisions of the code, including area and height & story limitations, fire protection systems, and means of egress components, are applied individually to the building on each side of the fire wall.

* not fire barrier (NCBC-706) or fire partition (NCBC-708)

Figure 9- The square footage of the covered outdoor space in the foreground shall be included in the aggregate square footage of the attached building in

the background.

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4. Additions separated by fire barriers are not considered separate buildings but are considered separate fire areas. Two areas separated with fire barriers are still considered as part of a single building, where as two areas separated by a fire wall or two exterior walls are defined as separate buildings. This distinction is critical in determining compliance with allowable height and area and other code provisions. The construction of a fire barrier may affect the requirement for sprinklers in the addition.

E. Determining if a Building Qualifies as “Non-Separated” or “Separated” Occupancies in a Mixed Occupancy Multiple Tenant Building

A building, usually with multiple tenant spaces that are classified with more than one occupancy group type use, can be designed as either non-separated or separated occupancies. 1. Non-Separated Occupancies (NCBC-508.3.2): Buildings with multiple tenant

uses not separated by fire barriers are considered non-separated occupancies and must comply with NCBC-508.3.2. If neither the covered outdoor space nor any existing tenant space(s) is separated by fire barriers (NCBC-706), the following steps can be applied to determine that the proposed covered outdoor area and the existing building does not exceed any of the NCBC limitation requirements in Section 503 and Table 503 (including associated footnotes under Table 503) to qualify as non-separated occupancies:

a. Determine the occupancy classification for the covered outdoor space and for each individual tenant space in the existing building (NCBC-Chapter 3). Refer to Section 5.0-A and 5.0-B of this document for additional information.

b. Determine which construction type or types apply to the covered outdoor space and to each individual tenant space in the existing building (NCBC chapter 6). The lowest construction type will be applied to the entire structure. (For example, if a portion of the building is Type II-A and the remaining area is Type V-B, the entire building is classified as Type V-B.) Refer to Section 5.0-C of this document for additional information.

c. Per NCBC-Chapter 5, determine the building area, the general building height and the number of stories (if more than one story). Also review Chapter 5 for exceptions to these requirements including any increases which can be obtained, for example, in area or height. Refer to Section 5.0-D of this document for additional information.

d. Apply all other Code requirements to each occupancy group, individually based on the specific occupancy type of each space. Examples include means of egress elements, exterior wall requirements, etc.

2. Separated Occupancies (NCBC 508.3.3): Different occupancies must be located

in separate fire areas (NCBC-508.3.3.4). They must be separated completely, both vertically by fire barriers (NCBC-Section 706) and horizontally by fire-resistant-rated assemblies (NCBC-Section 711). The following steps can be applied to determine if the project qualifies by the NCBC as separated occupancies:

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a. In accordance with Chapter 3 of the NCBC, determine which occupancy classification applies to the covered outdoor space and to each tenant space in the existing building. Refer to Section 5.0-A of this document.

b. Determine which area(s) of the building are separated into fire areas. The separation between fire areas is achieved with fire barriers as addressed in NCBC-Section 706 and, if more than one story, with horizontal assemblies as addressed in NCBC-Section 711. Determine the fire-resistance rating of the fire barriers and, if applicable, horizontal assemblies. Prescribed ratings shall be as required in NCBC-Table 508.3.3, including associated footnotes under Table 508.3.3.

c. The minimum type of construction for the entire building is determined by the height and area of the building for each occupancy classification in accordance with NCBC-Chapter 5 and NCBC-Table 503 (including footnotes below Table 503) as follows:

i. Compare the height, relative to the grade plain, of each fire area with respect to the most restrictive occupancy contained within that fire area to the height allowed by NCBC-Table 503 for a building in that occupancy type. See NCBC-Section 504 for exceptions to the to the height limitations of Table 503 for certain buildings, based on the building’s proposed occupancy classification and the fire safety features included in the design of the building.

ii. Determine the weighted average of areas occupied by the various occupancies in each fire area. For each story (if more than one story), the area of the occupancy shall be such that the sum of the ratios of the actual floor area of each occupancy type use, divided by the allowable floor for each occupancy type use per NCBC-Table 503, shall not exceed one (1). The area calculation formula for determining the allowable areas for each occupancy group is as follows:

Actual Area of Actual Area of Occupancy Type A + Occupancy Type B = < 1

Allowable Area for A Allowable Area for B

per NCBC-Table 503* per NCBC-Table 503*

* Note the following in regard to allowable area:

In the evaluation of allowable area, intervening fire barriers between different fire areas containing the same occupancy type are not a consideration. In determining the floor area per occupancy, all fire areas of the same group are added together.

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In determining the allowable areas for each occupancy group, the tabular areas from Table 503 can be modified in accordance with the provisions of NCBC-Section 506. Thus, the allowable areas are intended to include the increases obtained as result of sprinklers and frontage. Respective to the allowable frontage increase, use the entire building perimeter and not just the fire area perimeter. If considering the sprinkler increase, note that the entire building must be sprinklered, per Section 506.3, and not just a particular fire area.

d. Apply all other Code requirements to each fire area, individually based on

the occupancy or occupancies present (design occupancy load, means of egress elements, exterior wall requirements, etc.).

3. Fire Areas and Sprinkler Requirements: NCBC-706.3.9 addresses single-

occupancy fire areas. Since many of the fire suppression system thresholds, per NCBC-903.2, are based upon fire areas, separation of a single occupancy, such as A-2, into small fire areas can be an acceptable method for avoiding the use of sprinklers. If the separation is provided, each fire area may be evaluated separately for purposes of determining the applicable provisions of the NCSBC. NCBC-Table 706.3.9 provides the minimum required fire-resistance ratings of the fire barrier wall or horizontal assembly separating two fire areas of the same occupancy group. Refer to Section 5.0-G of this document for additional information.

F. Maintaining Means of Egress for the Existing Building During Construction of the Covered Addition

1. During alterations, additions and/or repairs, a building can be even more

vulnerable to an emergency event, and egress components or other fire protection features (sprinkler system, alarm system, etc.) cannot be temporarily compromised. This is a violation of the Code, as addressed in NCBC-Section 3302.

Example: The code requires a restaurant to have two exits and one exit may be temporarily closed during the construction of an uncovered or covered outdoor area. The restaurant continues to be opened for business during construction. Consequently, an alternate (temporary) code compliant 2nd exit shall be provided until such time as the original 2nd exit is reopened. At no time can only one exit be in operation, when 2 are required, when the building is occupied.

2. If any means of egress components or other fire protection features are to be affected temporarily during a construction project, a floor plan shall be submitted to the CEO which indicates how a code compliant equivalency will be addressed.

G. Fire Suppression Systems for the Existing Building and the Covered Addition Based on the Code in effect at the time the existing building was permitted, fire suppression systems may not have been required. However, the construction of a roof structure over an outdoor space adjacent to and serving the same use as a restaurant or nightclub may trigger the requirement for a sprinkler system throughout all new and

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Figure 10- Existing building with sprinkler system triggers covered outdoor space addition to also have compliant sprinkler

system.

existing spaces of the building that are not separated by fire barriers or separated by a fire wall. A review of NCBC-Chapter 9 is recommended as fire suppression systems may now be necessary for Code compliance. Threshold requirements for those systems can be triggered by occupancy classification, occupancy load, square foot area and/or level of exit discharge. (Figure 10).

Example: Under the 1994 Building Code (with 1996/1997 amendments), a restaurant with 100 to 999 persons was classified by occupancy as A-2 (Small Assembly) and was not required to have an NFPA 13 automatic sprinkler system. Current Code (NCBC-903.2.1.3 and NCFC-903.2.1.3) requires an NFPA 13 automatic sprinkler system for A-2 occupancies where one of the following conditions exists:

1. The fire area exceeds 5000 square feet;

or 2. The fire area has an

occupant load of 300 or more, except 100 for nightclubs*;

or 3. The fire area is located

on a floor other that the level of exit discharge.

*For additional information, refer to the White Paper by Evaluation Services Section entitled “Sprinkler Requirements for Nightclubs Nov 2010” that is located on the NCDOI-OSFM website at the following link: http://www.ncdoi.com/OSFM/Engineering/engineering_wpt.asp

H. Plumbing Fixtures for the Existing Building and the Addition of an Uncovered Outdoor Area or a Covered Addition

The addition of an uncovered or a covered outdoor space to serve an existing restaurant, etc. will increase the design occupancy load of an existing building. The plumbing fixture count shall be re-evaluated as follows for compliance with the current NCPC (Chapter 4) and NCBC (Chapter 29):

Option # 1 – Addition only (uncovered or covered): Provide additional plumbing fixtures for the calculated occupant load, under the current NCPC, for the addition to accommodate the increase in the occupancy load for males and

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females created by the construction of the uncovered outdoor area or covered outdoor space;

or

Option # 2 – Existing plus Addition (uncovered or covered): Calculate the design occupancy load for the uncovered outdoor area or the outdoor covered space plus the calculated load for the existing restaurant or bar, under the current NCPC, to determine the total fixture count required for males and females. If the number of existing plumbing fixtures is deficient by calculation to accommodate the addition plus the existing space, provide additional fixtures to comply with the revised fixture count.

I. Energy Requirements for the Covered Addition Unless a covered outdoor building space complies with the minimum commercial building thermal envelope requirements of the NCEC, a permanent heating and/or cooling appliance is not allowed to be installed to serve this space. Also, duct work is not allowed to be extended from the existing building to serve the covered outdoor addition. (Figure 11). DOI is unaware of any plastic or fabric enclosures, as addressed in 5.0-L of this document, that comply with the Energy Code requirements at this time. The 2012 NCEC does contain a provision to

allow outdoor comfort heating. The provision in the 2012 NCEC indicates “Systems installed to provide heating outside a building shall be radiant systems. Such heating systems shall be controlled by an occupancy sensing device or a timer switch, so that the system is automatically de-energized when no occupants are present.” (Figure 12).

J. Structural Requirements for the Covered Addition

Roof and wall structures, including roof covering, for covered outdoor spaces shall be designed and constructed to withstand

Figure 11-Extending existing duct work from existing building to serve covered outdoor space is not allowed by

the NCEC.

Figure 12- Example of a permanent radiant

heating appliance.

DOI File # WP-009-11 Covered Outdoor Space Adjacent to Restaurant or Bar Page 16 of 17

wind or other lateral loads, snow loads and live loads as required by NCBC-Chapter 16, with due allowance for shape, open construction and similar features that relieve the pressures or loads. Wind uplift is particularly important in the design of open sided covered structures. Weight required to hold the structure down may control the foundation design. See NCBC-Table 1607.1 for minimum roof live loads.

K. Guards at the Covered Addition If any edge of the finished floor of the outdoor space is more than 30” above finish grade, guard rails are required around the perimeter where this condition occurs. Requirements for guards are addressed in Section 1013 of the NCBC.

L. Pliable Light Transmitting or Fabric Curtain System for Weather Protection at the Covered Addition

For weather protection, a pliable light transmitting or fabric curtain system may be located in openings between columns around the exterior perimeter of covered outdoor spaces. (Figure 13). Code requirements for these systems are addressed in the White Paper by the Evaluation Services Section entitled “Pliable Light Transmitting or Fabric Curtain System for Weather Protection at a Covered Outdoor Space” that is located on the NCDOI-OSFM website at the following link:

http://www.ncdoi.com/OSFM/Engineering/e

ngineering_wpt.asp

M. Accessibility Requirements for the Covered Addition This document does not specifically address handicap accessibility code components. However, compliance with the NCBC continues to be required. For example, new required exits serving the covered outdoor space are required to be accessible, as addressed in NCBC-Section 1007.1.

Figure 13-Example of fabric curtain system with pliable light

transmitting material.

DOI File # WP-009-11 Covered Outdoor Space Adjacent to Restaurant or Bar Page 17 of 17

6.0 REFERENCES

Special uses and Mixed Occupancies, February 2001, by the Building Officials and Code Administrators International, Inc.

2003 IBC Architectural Applications for Designers, August 2004, by the International Code Council, Inc.

2006 International Building Code Commentary, September 2006, by the International Code Council, Inc.

7.0 PHOTO RESOURCES

Figure 1- Patio Enclosure

Figure 2- Retractable cover

Figure 3- Taken By NCDOI

Figure 4- Taken By NCDOI

Figure 5- http://www.litrausa.com/Restaurant_Enclosures-12.html Figure 6- Mixed use strip mall

Figure 7- Roll-a-Cover

Figure 8- Taken By NCDOI

Figure 9- Taken By NCDOI

Figure 10- Taken By NCDOI

Figure 11- Taken By NCDOI

Figure 12- Taken By NCDOI

Figure 13- Taken By NCDOI

This document does not constitute an evaluation of any vendor’s product nor does this document imply that the Code Enforcement Official must approve any specific material, design or method.