Strange Observations – Gypsum Patches

Continuing in a series of strange things that I have seen while consulting at hospitals…

Holes in rated walls that are too large to be sealed with fire-rated materials, cannot be ‘fixed’ with a gypsum board patch, as shown in the picture.

However, there is a UL system W-L-0014 that does permit installing gypsum patches over holes in rated walls, but it requires an equal-sized patch on the opposite side of the wall, along with other requirements, such as 3-inch long screws with fender washers. The W-L-0014 system is part of the Hilti Firestop System library of listed products.