BCAB #1307 - Insulation Above Pot Lights, Article 188.8.131.52
May 19, 1993
Re: Insulation Above Pot Lights, Article 184.108.40.206
The project in question is a pair of additions to a single family dwelling located in an area with a January 2.5% design temperature of -6C. A large number of pot lights are installed in the vaulted ceilings of the additions and at each pot lamp location the thermal insulation is reduced from R-28 fibreglass batts to R-12 rigid foam board.
Reason for Appeal
Article 220.127.116.11. of the 1985 B.C. Building Code requires that buildings of residential occupancy be provided with sufficient thermal insulation to prevent condensation on the interior surfaces of walls, ceilings and floors during the winter months.
The appellant contends there is sufficient insulation above the pot lights to meet the requirements of Article 18.104.22.168.
Building Official's Position
The building official is concerned that condensation and possibly ice bridging could occur above the pot lights and the condensation would be difficult to detect.
Appeal Board Decision #1307
It is the determination of the Board that if ice damming is considered a potential problem for the areas around the pot light fixtures, appropriate provisions should be made to prevent damage as required in Article 22.214.171.124.
In the detail drawings submitted a ceiling vapor barrier and "vapor barrier bag" enclosing each pot light fixture is indicated. Provided these components and any penetrations are sealed in accordance with Article 126.96.36.199., the assembly meets the Building Code requirements for vapor barrier protection. The building official states "none have been sealed", therefore this matter of site compliance should be resolved with the building official and the appellant.
Sentence 188.8.131.52.(1) requires that there be a "reasonably uniform insulating value over the entire face of the insulated area." The Board considers the reduction of insulating value above the potlight fixtures would fall within the intent of "reasonably uniform" in relation to the entire insulated roof area. This decision is predicated on the building falling within the scope of Section 9.25. of the Building Code.
George R. Humphrey, Chair