Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

3 Hour Fire Rated Ceiling Assembly

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Title: 3 Hour Fire Rated Ceiling Assembly

I have a 40 ft x 28 ft single story wastewater treatment building that is classified F-1 except for a small area which is classified H-2 because of some process considerations. The building code requires a 3-hour fire separation between the occupancies.

The building is CMU with timber trusses and plywood roof sheathing. The bottom chord is about 10 ft off the floor. I plan to enclose my H-2 area with 8 CMU walls, which gives me the required rating for the walls, and provide a 3 hour rated ceiling over the H-2 room with a ceiling height of about 8-8. I was thinking I could use cold formed steel joists with maybe three layers of 5/8 Type X GWB attached to metal runners under the joists, but I cant find anything like that thats a pre-approved system. I would like to avoid having to cast a heavy concrete slab over the room just to get the fire resistance. I could avoid the problem by just calling the whole building an H-2 occupancy, which would make the separation requirement go away, but I think that would trigger more expensive electrical work in the non-hazardous area.

Anybody have experience with simple 3-Hour rated ceiling systems that dont involve concrete slabs?

Jim Lutz, P.E., S.E.

720 3rd Avenue, Suite 1200

Seattle, WA 98104-1820

206 505 3400 Ext 126

206 505 3406 (Fax)