How to modify a tested fire-rated wall to improve its stc sound rating, while maintaining its official fire-rated qualification

摘要

Underwriters Laboratories Canada (ULC) has issued design guidelines for fire ratings that outline modifications that are permitted to a tested design that do not affect the tested fire rating. Under the guidelines the dimensions and gauge of steel studs are minimums and additional layers of gypsum board are permitted to be added to any design. It also state that Listed and labeled mineral fibre thermal building insulation processed from rock, slag and glass only may be used in ULC non load-bearing wall assembly designs consisting of wallboard and steel or wood studs with a fire-resistance rating not exceeding two hours when illustrated without insulation, without detracting from the rating assigned to the assembly. In a specific example of modifying a wall, a mechanical shaft within a condo needed a 2 hour fire rating as well as a high STC rating of 62.