BCAB #1530 - Mezzanines Considered as a Storey in Building Height, Sentence 188.8.131.52 (3)
March 22, 2001
Re: Mezzanines Considered as a Storey in Building Height, Sentence 184.108.40.206 (3)
The subject building is an assembly occupancy which incorporates a hall area of 400 m2 with a mezzanine within the hall area. The total area of mezzanine is 70.5 m2 (17.6% of the area below) and runs continuously the full length (side) of the hall. The edge of the mezzanine overlooking the hall area below is constructed as an opaque wall, continuous from floor to ceiling, with four large openings. If from each end of each opening a line is projected back 90 degrees to the back wall of the mezzanine, these lines would bound an area behind the opaque portions of the wall which are being considered as "enclosed". The cumulative area of all of these "enclosed" areas is 40 m2 (10% of the area below).
Reason for Appeal
Sentence 220.127.116.11.(3) requires as one of the conditions when a mezzanine is not considered to be a storey in building height, that there be no visual obstructions between 1070 mm and 2150 mm above the floor.
The appellant contends the Code permits a cumulative enclosed area of the mezzanine up to 10% of the suite they are located in. As the areas described are not completely enclosed, but only visual obstructions to the area below, this circumstance provides a higher level of safety as compared to what the Code permits. The appellant does not consider the mezzanine to be a storey when determining building height.
Building Official's Position
The Building Official considers the visual openness requirement of Clause 18.104.22.168.(3)(b) to the floor below is being compromised by the construction of the full height opaque wall interspersed with openings. The Building Official considers the mezzanine to be a storey when determining building height.
Appeal Board Decision #1530
It is the determination of the Board that the mezzanine as proposed complies with Sentence 22.214.171.124.(3) and is not considered a storey in building height. The Board considers the areas behind the opaque portions as being "enclosed". In this case the Board also considers the areas behind the openings meet the intent of the visual requirements of Clause 126.96.36.199.(3)(b).
George Humphrey, Chair