BCAB #1319 - Combustible Water Pipe in Concrete Floor Slab, Sentences 3.1.7.2.(1) & 3.1.7.2.(4)

August 19, 1993

BCAB #1319

Re: Combustible Water Pipe in Concrete Floor Slab, Sentences 3.1.7.2.(1) & 3.1.7.2.(4)

Project Description

The project in question consists of an 18 storey apartment building and a 21 storey apartment building, both of poured-in-place concrete construction. The appellant proposes to install combustible polybutylene water distribution piping in polybutylene conduit cast into the concrete floor slabs. This combustible pipe would be connected to noncombustible copper risers via copper headers in each suite. The polybutylene pipe would be used only within the suites, would not penetrate completely through the horizontal fire separations (floors) and would have at least 50 mm of concrete cover below it.

Reason for Appeal

Sentence 3.1.7.2.(1) of the 1985 B.C. Building Code requires "...pipes...that partly...penetrate an assembly required to have a fire resistance rating shall be noncombustible unless the assembly has been tested incorporating such equipment." An exception to this requirement is Sentence 3.1.7.2.(4) which permits combustible conduit to be embedded in a concrete floor slab with a fire resistance rating providing there is at least 50 mm of concrete below the conduit. There is a disagreement as to whether or not these two Sentences permit the proposed water distribution pipe installation described above.

Appellant's Position

The appellant contends that because the polybutylene pipe does not pass through the concrete floor it should be permissible under Sentence 3.1.7.2.(4) because it is the same as combustible conduit. The metal conduit into which the polybutylene pipe will be pulled is only to allow future removal and repair and is not related to fire resistance.

Building Official's Position

The building official maintains that the polybutylene water pipe penetrates the concrete floor slab and Sentence 3.1.7.2.(1) only permits this if the floor slab has been subjected to the fire resistance test with the inclusion of the polybutylene pipe.

Appeal Board Decision #1319

It is the determination of the Board that because the pipe partly penetrates the fire rated floor assembly, Sentence 3.1.7.2.(1) does not permit the combustible water distribution pipe to be embedded in the concrete floor slab unless such an assembly has passed the fire resistance test.

George R. Humphrey, Chair