BCAB #1800 - Re: Requirements for Interconnected Floor Spaces

October 4, 2017

BCAB #1800

Re: Requirements for Interconnected Floor Spaces

Project Description

The subject building is an existing three-storey sprinklered building containing offices and classrooms, to which a two-storey horizontal addition is proposed. To create a courtyard effect, the proposed addition includes two openings through the floor assembly between the first storey and second storey; a large opening approximately 16.5 m X 26.8 m and a small opening approximately 2.1 m wide by 7.5m long to accommodate a stair. The proposed interconnected floor space complies with the conditions of Sentence 3.2.8.2.(6). The subject of this appeal is whether draft stops and close spaced sprinklers are required at the perimeter of the openings.

Applicable Code Requirement

• Sentence 3.2.8.2.(6) of Division B of the 2012 British Columbia Building Code

3.2.8.2.(6) An interconnected floor space need not conform to the requirements of Articles 3.2.8.3. to 3.2.8.9. provided

a) the interconnected floor space consists of the first storey and the storey next above or below it, but not both,

b) the openings through the floor are used only for stairways, escalators or moving walks or the interconnected floor space is sprinklered throughout (see Appendix A),

c) the interconnected floor space contains only Group A, Division 1, 2 or 3, Group D, Group E, or Group F, Division 2 or 3 major occupancies (see Appendix A), and

d) the building area is not more than one half of the area permitted by Sentence 3.2.2.

• Paragraph 8.15.4.  NFPA 13, “Installation of Sprinkler Systems,” 2013 Edition referenced in Sentence 3.2.5.12.(1) of Division B of the 2012 British Columbia Building Code

8.15.4 Vertical Openings

8.15.4.1 General. Unless the requirements of 8.15.4.4 are met, where moving stairways, staircases, or similar floor openings are unenclosed and where sprinkler protection is serving as the alternative to enclosure of the vertical opening, the floor openings involved shall be protected by closely spaced sprinklers in combination with draft stops in accordance with 8.15.4.2 and 8.15.4.3.

A-8.15.4.1 It is the intent of this section to require closely spaced sprinklers and draft stops to openings where protection or enclosure is required by building and life safety codes.

8.15.4.4 Large Openings. Closely spaced sprinklers and draft stops are not required around large openings such as those found in shopping malls, atrium buildings, and similar structures where all adjoining levels and spaces are protected by automatic sprinklers in accordance with this standard and where the openings have all horizontal dimensions between opposite edges of 20 ft. (6 m) or greater and an area of 1000 ft² (93 m²) or greater.

Decision being Appealed (Local Authority’s Position)

The local authority has determined that draft stops and closely spaced sprinklers are required for the subject interconnected floor space openings in accordance with the NFPA 13 standard.

The local authority bases the decision on:

• The requirement of Clause 3.2.8.2.(6)(b) that an interconnected floor space to be sprinklered throughout is considered to be required protection for the opening and is an alternative to an enclosure required by the Building Code,
• Sentence 3.2.5.12.(1) directs the design and construction of sprinkler systems to comply with the NFPA 13 standard,
• 8.15.4.1. (including Annex A A.8.15.4.1.) of NFPA 13 applies and requires the interconnected floor space to be protected by draft stops and closely spaced sprinklers where sprinkler protection is serving as the alternative to the enclosure of the opening.

Appellant's Position

The appellant maintains that neither the BC Code nor the referenced NFPA 13 standard require draft stops or close spaced sprinklers surrounding the opening of an interconnected floor space described in Sentence 3.2.8.2.(6).

Appeal Board Decision #1800

It is the determination of the Board that draft stops and close spaced sprinklers for the interconnected floor space openings are not required by the BC Building Code or the Code’s application of the referenced NFPA 13 standard.

Reason for Decision

The Board considers Article 3.2.8.2. “Exceptions to Special Protection” to be unique to the BC Building Code and may not directly coincide with specific requirements of the Code’s referenced standard     NFPA 13. The exceptions for protection of interconnected floor spaces of Article 3.2.8.2. would supersede any differing requirements of the NFPA 13 referenced standard. The Board also recognizes a difference in terminology between the two documents.

As the subject large interconnected opening of 16.5 m X 26.8 m complies with the conditions of Clause 3.2.8.2.(6)(b), the BC Building Code exempts the requirements for draft stops of Article 8.2.8.7. Further, as the opening meets the conditions of 8.15.4.4. Large Openings of the NFPA 13 standard, this exempts its requirements for closely spaced sprinklers and draft stops.

For the small interconnected opening incorporating the stairway, this opening complies with the conditions of Sentence 3.2.8.2.(6) which exempts the requirements for draft stops of Article 8.2.8.7.  In this circumstance the Board equates the interconnected opening to be similar to that of a “communicating space” or “convenience opening” as described in NFPA. For these applications NFPA 13 does not require draft stops and closely spaced sprinklers. Further, as this interconnected opening is only 0.5 m wider than the stairway within, it may be considered the interconnected floor space could comply with the conditions of Clause 3.2.8.2.(6)(b) without being sprinklered throughout.

The Board is aware of and supports the present work of the National Research Council Standing Committee on Fire Protection Working Group to provide clarification of the Building Code and NFPA 13 requirements for the protection of interconnected floor spaces.

Lyle Kuhnert
Chair, Building Code Appeal Board