Know Your Enemy #49

We continue with our pictorial discussion of trusses which started with Know Your Enemny #44, Previous units are archived HERE.

Photo By Frank Brannigan

Photo R277 - Post WWII Garden Apartments had small rooms and thus closely spaced interior partition walls. During a roof collapse of these buildings, it is common to see the roof resting on the closely spaced interior partition walls.

Photo R278 - In a wide span commercial or residential building, the entire roof will fall trapping firefighter in flaming lumber. The best RIT or FAST team may be unable to rescue victims in time.

Photo By Frank Brannigan

Photo By Frank Brannigan

Photo R296 - Heavy loads are often carried on a GRILLAGE, a group of closely spaced beams. In this case trusses were doubled up to carry the load of the air conditioner. This design gives no more protection to firefighters as both trusses will be burning at the same time.

Photo R272 - This gusset plate is made of a sheet of steel from which bottle caps were cut out, and is attached with nails. Take note of what goes into the building, and what is done with damaged trusses. Are they discarded or patched up?

Photo By Frank Brannigan