Floor Trusses

I need to obtain some information on fire-retardant-treated roof trusses.

The Gypsum Association “Fire Resistance Design Manual” (GA-600-12) lists file RC2601 with two layers of 5/8 in. gypsum wallboard (GWB) on wood joists.

In our one-year-old home, as you approach the hallway, the floor slopes downward. Our home inspector said that this was most likely due to the fact that the walls were resting on the floor as opposed to being load-bearing walls. What has been your experience with sloping floors in a new home? The floors are very flat elsewhere until the walls start. Do you think this sloping could turn into a structural problem eventually?

While building a new 2-story home, I found the need to use floor trusses between the 1st and 2nd floors. Is it true that I must also use roof trusses?

How do trussed roofs perform in long-term service? Are there any reports of rusting in the nail plates, rot/insect attack, do-it-yourself modifications, or condensation and ventilation problems in the attic?

Is it common practice for the supplier/distributor of a truss to provide a publication regarding temporary bracing with the delivery of the material?

What do you mean by the term “trusses”? Are there different kinds of trusses? What are their uses?

I have been told that the high temperatures and low humidity present in attics can cause deterioration of wood, leading to truss failure. Is this true? If so, what length of time are we looking at and can we see the deterioration in the wood by visual inspection?

Are there any trusses that are supported strictly by the wood itself without any mechanical connections such as brackets?

What tolerances are allowed for metal plate connectors in wood trusses? How do you take into account the possible presence of splits, waves and knots?