BCAB #1916

October 5, 2023

Re: Glazed Openings in Exposing Building Face of a Single Family Dwelling

Project Description

The project consists of a new single family dwelling located in an area where the fire department response time exceeds ten minutes. The building is not sprinklered and one exterior wall is located 1.5m from the adjacent property line. The design of the exterior wall includes a bedroom window and a bathroom window.

Applicable Code requirements (BCBC 2018)

Article 9.10.15.3., Division B, Limiting Distance and Fire Department Response
1) Except for the purpose of applying Sentences 9.10.15.2.(2), 9.10.15.4.(3) and 9.10.15.5.(13), a limiting distance equal to half the actual limiting distance shall be used as input to the requirements of this Subsection, where [. . .]

Article 9.10.15.4., Division B, Glazed Openings in Exposing Building Face
3) Except for buildings that are sprinklered and for openable windows having an unobstructed opening equal to 0.35 m2 installed in accordance with Sentences 9.9.10.1.(1) and (2), where the limiting distance is 2 m or less, individual glazed openings or a group of glazed openings in an exposing building face shall not exceed 50% of the maximum allowable aggregate area of glazed openings determined in Sentence (1).

Decision being appealed (Local Authority’s position)

Based on the exception provided in Sentence 9.10.15.3.(1) and, therefore, using the actual limiting distance of 1.5m, Sentence 9.10.15.4.(3) permits the bedroom egress window.

A reduced limiting distance of 0.75m applies to the bathroom window because the same exception cannot be applied.

Appellant's position

Sentence 9.10.15.3.(1) exempts Sentence 9.10.15.4.(3) with the result that, for limiting distance of 2m or less, the actual limiting distance can be used and the resulting permitted area of glazed opening is then reduced by 50%. Based on the exemption provided in 9.10.15.4.(3) the bedroom window is permitted and the calculation only applies to the bathroom window.

Appeal Board Decision #1916

The Board varies the decision of the Local Authority. It is the determination of the Board that no glazed openings, including the bedroom window, are permitted in the exposing building face having a reduced limiting distance of 0.75m.

Reason for decision

Sentence 9.10.15.4.(3) limits the concentration of permitted glazed openings when the limiting distance is 2m or less. Sentence 9.10.15.4.(3) does not stipulate the maximum allowable aggregate area of glazed openings. The exception within Sentence 9.10.15.4.(3) allows a bedroom window, as an
individual glazed opening or as part of a group of glazed openings, to exceed 50% of the maximum allowable aggregate area of glazed openings.

If the calculation allowed for any glazed openings, the bedroom window would be permitted to exceed the 50% limitation as an individual opening or as part of a group of openings. However, in this case there are no glazed openings permitted based on the reduced limiting distance.

Don Pedde
Chair, Building Code Appeal Board