fire wall - existing pre-eng bldg

[rittz]

A Contractor friend of mine erected a pre-engineered steel building. The inspector informed him that it violated the limiting distance requirements on the side wall and wants a two hr rating on the side wall (160 ft long x 18 ft eave ht). The building is a typical pre-eng with rigid frames at 20 oc, w/ girts and 24 gage o/s sheeting. Has anyone had to do something like this after the fact.

There is a jog in the wall so that half of it requires only 1-hr rating

 

[a2mfk]

seems more like an architectural question unless you are asking us about designing some type of break away wall....?

 

[Ron]

What is the building occupancy and classification?

 

[ajh1]

Check out UL fire ratings U425, U489, and V421.
Each of those has the potential of a 2-hour rating with an appropriate number of layers of drywall. Note that if you are needing a rating for an exterior fire source it may be necessary to get a layer of drywall between the girts and the exterior siding. (Obviously problematic on an existing structure).