Rated roof/ceiling assembly

[duckbill]

R-2 apartment building with separation of units by fire partition terminating at a fire-resistance rated roof/ceiling assembly, UL P533. Apartment building is 30 feet wide with 46 feet trusses creating an 8 feet porch (open) on each side of the building. The building interior is constructed to the assembly requirements with rc channel and rated dry wall. Should the porches have the same ceiling construction? Is the rated roof/ceiling assembly required to cover the entire bottom chord of the truss?

 

[cda]

is the rating only required for each apartment unit???

 

[fatboy]

Where is the bearing point for the trusses? Exterior wall of the unit, or at the outside of the open porch?

If it is the exterior of the porch, then I would say it definitely needs protection to the bearing point.

 

[duckbill]

cda, that was my question actually. The apartment units are separation by fire partitions terminating at a fire-resistance rated roof/ceiling assembly, UL P533. My question was, does the entire underside of the truss need constructed to UL P533, which would include the porch areas, or just the apartments themselves.

fatboy, that makes sense even though the contractor and owner will not agree.

 

[mark handler]

As stated, to the bearing points, if that is the porch/patio then it must be protected.

Who's to say the renter will have a BBQ fire on the porch/patio then, with no protection, the entire complex is ablaze