FIREPRROOFING TIMBER 3

[sigma1]

WE HAVE AN OLD MILL (TIMBER)STRUCTURE AND THE OWNER WOULD LIKE TO USE THE SECOND FLOOR FOR MISC. METALS FABRICATION SHOP. TO FIREPROOF AND PROTECT THE WOODEN FLOOR AND THE BEAMS BELOW THEY ARE THINKING OF PLACING A LIGHT WEIGHT CONCRETE SLAB OVER THE HARDWOOD FLOORS. DOES THIS PRESENT A FIRE HAZARD PROBLEM? IS THERE ANOTHER WAY TO FIREPPROOF THE HARDWOOD FLOOR AND TIMBER BEAMS BELOW? IT IS A 2 STORY BUILDING WITH STEEL COLUMNS

 

[RARWOOD]

Consult the local building official. I would think that the light weight topping would protect the wood, but I do not know how a code official would treat the problem.

In addition to the light wieght topping you might also look at the use of a spray on coating. The use of a coating could reduce flame spread and in some cases reduce the combustability of the timber.

 

[SperlingPE]

See the UL Design book. There are rated assemblies shown in there.
I don't think a light weight concrete topping by itself will provide adequate fireproofing.
It could also depend on the size of the timber (not wood) members. If wood construction, some combination of spray-on or gwb construction will probably be needed.

What is required? One hour? Two hour?

 

[Lion06]

Are the beams below wood, also? If so, I would think that even a lightweight topping slab might pose a significant burdern to the wood framing.