BCAB #1266 - Electrical Wiring Penetrating Fire Separations, Sentences 3.1.7.2.(1), (2) & (3), Article 9.10.9.10.

November 21, 1991

BCAB #1266

Re: Electrical Wiring Penetrating Fire Separations, Sentences 3.1.7.2.(1), (2) & (3), Article 9.10.9.10.

Project Description

A wood frame apartment building constructed under Part 3 of the Building Code.

Reason for Appeal

Sentences 3.1.7.2.(1), (2) & (3) and Article 9.10.9.10. control the penetration of fire resistant wall and floor assemblies by services such as electrical wires and conduit. Providing wires are enclosed in noncombustible conduit there is basically no restriction in Part 3 or Part 9 with penetrating fire rated walls and floors. Combustible wiring not in metal conduit and not exceeding 25 mm in diameter is permitted by Sentence 3.1.7.2.(3) to penetrate walls but not floors whereas Article 9.10.9.10. allows penetration of any fire separation.

Appellant's Position

In a wood framed Part 3 building, the appellant has followed Part 9 practice of penetrating fire rated walls and floors with standard NMD-90 nylon covered electrical conductors. He considers the inconsistency in requirements between Part 3 and Part 9 buildings of the same construction type to be unreasonable and feels that design and installation conforming to Article 9.10.9.10.should be acceptable.

Building Official's Position

The building official maintains that the Code is quite clear and does not permit combustible wiring to wholly or partly penetrate a horizontal fire separation in a Part 3 building unless contained in noncombustible conduit or it is shown that the penetration conforms to the fire resistance test, ULC S-101.

Appeal Board Decision #1266

Although the Board members agree there is a difference between Part 3 and Part 9 of the Code regarding penetration of fire rated floor assemblies by wiring with combustible insulation or jacketing the Board cannot change the Code or allow a variance from it. The Board considers that Article 3.1.7.2. prohibits wiring with combustible insulation or jacketing from partly or wholly penetrating fire rated floors (horizontal fire separations) unless contained in noncombustible conduit. As this building is designed and constructed under Part 3 the conduit is required.

George R. Humphrey, Chair