Working on an existing renovation project in NYC that requires a 1-hr fire rating between occupancies. There is an existing 5 1/2" concrete slab between the floors requiring the separation - can't seem to find in code whether this might be an acceptable separation as most of the data I'm seeing seems to show we should be above 1 hr with that thickness of concrete. Would love to keep the ceilings exposed if possible.
Anyone have any experience with this?
Non Sequitur
May 9, 18 12:59 pm
Without a steel deck, your rating is as good as the thickness of the concrete at the rebar. Get the floor scanned and work backwards from there.
okaydee
May 9, 18 1:28 pm
Sorry, should have clarified this is concrete on metal decking. 5 1/2" at largest depth. I guess the main question is, can you apply a UL listing to an existing assembly? Would we need to have the existing concrete material tested to verify its composition.
Rusty!
May 9, 18 1:50 pm
How are you getting a 1 hour floor rating for a concrete floor building?
IBC Table 720.1 has 1 hour concrete floor @ 3.5-inch, and 2 hour @ 5 inch.
You probably need 2 hour rating.
Non Sequitur
May 9, 18 1:52 pm
There should be UL systems available for this since they don't specify that all component of each assembly ought to be new. Find one that meets the existing floor's composition.
Working on an existing renovation project in NYC that requires a 1-hr fire rating between occupancies. There is an existing 5 1/2" concrete slab between the floors requiring the separation - can't seem to find in code whether this might be an acceptable separation as most of the data I'm seeing seems to show we should be above 1 hr with that thickness of concrete. Would love to keep the ceilings exposed if possible.
Anyone have any experience with this?
Without a steel deck, your rating is as good as the thickness of the concrete at the rebar. Get the floor scanned and work backwards from there.
Sorry, should have clarified this is concrete on metal decking. 5 1/2" at largest depth. I guess the main question is, can you apply a UL listing to an existing assembly? Would we need to have the existing concrete material tested to verify its composition.
How are you getting a 1 hour floor rating for a concrete floor building?
IBC Table 720.1 has 1 hour concrete floor @ 3.5-inch, and 2 hour @ 5 inch.
You probably need 2 hour rating.
There should be UL systems available for this since they don't specify that all component of each assembly ought to be new. Find one that meets the existing floor's composition.