Fire Resistance

Since FRTW studs are allowed in wall assemblies that are otherwise defined as non-combustible, building and truss designers often confront the question does a joint between the wall and the roof or floor assembly mean that those elements of the building also require noncombustible material, like FRTW? To answer this, we need to study the IBC

This presentation seeks to explain how to correctly apply live loads to the bottom chord of trusses for uninhabitable attics in accordance with IRC Table R301.5 and IBC Table 1607.1 and ASCE 7-10 Table 4-1.

This report focuses on building code requirements for using fire retardant treated wood (FRTW) in floor/ceiling and roof/ceiling assemblies in Type III building construction. 

This research report will focus on manufacturer or trade association deflection requirements for a number of floor topping/covering related products where deflection requirements may impact serviceability.

This presentation provides an overview of fire-rated assemblies that include wood trusses. Topics covered include assembly testing, Harmathy’s rules, and an examination of fire performance in the field. 

Our home caught fire last month and burned partly through a tongue and groove ceiling to the trusses. Some are charred. Our contractor did a moisture meter test. An engineer for the insurance company said the trusses were only smoke damaged & the moisture meter test is invalid (it can be set to read anything). I found one article on charred trusses, but it’s pretty vague. We do not feel safe with the insurance engineer’s assessment because some of the trusses are obviously charred. We hired an engineer who agreed with us.

Is a Class A fire rating (provided by our liquid spray-on fire retardant) acceptable in certain situations?

I have mono trusses on either side of a firewall. I have the fire rating/wall material between them. Can I place a ridge vent above these two? Or should I use vents? How do I calculate the appropriate vent sizes and styles?

I am looking for a 1-hour roof/ceiling assembly for wood truss construction. I would like to apply the drywall directly to the bottom of the truss and also have insulation for sound control. Is this possible without using channels and what UL number would I use?

We have a local builder wishing to use floor trusses with a 2-hour assembly. I have shown him the 2-hour design on pages 17-27 of the second edition of SBCA’s Metal Plate Connected Wood Truss Handbook. Is this assembly UL approved? If so, what is the design number?