BCAB #1482 - Tempering of Ventilation Make-up Air, Sentence 9.32.3.4.(3) ('92 BCBC)

April 21, 1999

BCAB #1482

Re: Tempering of Ventilation Make-up Air, Sentence 9.32.3.4.(3) ('92 BCBC)

Project Description

The project in question is a seniors apartment building. The suites are mechanically ventilated as required by Subsection 9.32.3. using the bathroom fan controlled by a humidistat. Make-up air is provided through two five inch diameter through-wall vents. One make-up vent is located in the bedroom closet ceiling and the other in the living room ceiling near the gas fireplace.

Reason for Appeal

Clause 9.32.3.4.(3)(a) requires make-up air in locations where the winter design temperature is not less than -10 °C to be tempered by being ducted into secondary areas such as utility or storage rooms, specially designed individual room or space through-wall diffusers, methods intended for locations where the winter design temperature is less than -10°C or other acceptable methods.

Appellant's Position

The appellant contends that the method of providing make-up air in the suites in this building complies with Clause 9.32.3.4.(3)(a). The five inch diameter vents are "specially designed through-wall diffusers" and one of them also discharges into a secondary area, the bedroom closet.

Building Official's Position

The building official maintains that the appellant's approach to mechanical ventilation does not meet the requirements of the code because the make-up air is not tempered before it enters the suite.

Appeal Board Decision #1482

It is the determination of the Board that the make-up air installation complies with the requirements of the code. The air is tempered by being introduced into the suite in conformance with Subclauses 9.32.3.4.(a)(i) and/or (ii).

George R. Humphrey, Chair