December 16, 2010
BCAB #1685
Re: Wire Mesh Guard, Article 9.8.8.6.
Project Description
This appeal concerns the use of welded wire mesh with a 1.5” x 1.5” (38 mm x 38 mm) grid in a residential guard. The welded wire mesh is contained within a frame ¾” metal angle which in turn is mounted between 2 x 6 (on edge) top and bottom rails between 6 x 6 posts.
Reason for Appeal
Sentence 9.8.8.6.(1) requires guards for residential occupancies to be “designed so that no member, attachment or opening will facilitate climbing.” Sentence 9.8.8.6.(2) then states that where a guard conforms to any of four measurable characteristics, in the area between 140 mm and 900 mm above the walking surface, it shall be “deemed to comply with Sentence (1).” The measurable characteristics are elements that protrude from the vertical and are more than 450 mm apart both vertically and horizontally, provide not more than 15 mm horizontal offset, provide a toe space not more than 45 mm horizontally and 20 mm vertically or have more than a 1-in-2 slope.
Appellant’s Position
The appellant contends that although the 1.5” square mesh exceeds the 20 mm vertical dimension for allowable openings it does not facilitate climbing because of the significant discomfort that would be experienced trying to climb the mesh in bare feet. It seems unlikely that even a small child could get their shoe into such a small opening. A 1.5” square mesh would seem to meet the objective of Sentence 9.8.8.6.(1).
Building Official's Position
The building official maintains that the that the 38 mm square welded wire mesh does not conform to either 9.8.8.6.(2)(a) or (c). The openings are closer than 450 mm apart and the 38 mm height exceeds the 20 mm limit.
Appeal Board Decision #1685
It is the determination of the Board that the 1.5” square mesh does facilitate climbing so does not conform to Sentence 9.8.8.6.(1) and more specifically does not conform to the maximum opening dimensions in Clause 9.8.8.6.(2)(c).
George Humphrey, Chair