Lumber Treatments

Fire-Retardant Treated Lumber Use: Ceiling Assemblies in Type III Buildings

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. 

Fire Rating For Truss Assemblies Built With 2x3 Lumber

Question: 

Are there any published studies or guidelines on the fire rating of floor trusses built with 2x3 lumber?

Fire Damaged Trusses

Question: 

I have been hired by an insurance company to determine the extent of damage to roof trusses exposed to fire. How much fire damage compromises the structural integrity of the truss?

Information On Frt Roof Trusses

Question: 

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

Wood Three Hour Fire Assembly

Question: 

Is it possible to construct an assembly for ceiling between first and second floors using 2x with few layers of gypsum to obtain a 3-hour fire rating?

Sprinklers Above Gypboard Ceiling

Question: 

I have a 29 x 72 mobile office with a 2-foot deep wooden truss above the ceiling that a client is required to sprinkler. Is there any way to avoid sprinklering above the gypboard ceiling?

Substituting Fire Rated Wood Truss Assemblies For Light Gauge Steel

Question: 

We recently received bids on a school project, which referenced UL P523. This assembly used light-gauge steel trusses. We noted on the drawing that we could accept an alternate design using wood trusses in lieu of light-gauge steel framing, if the alternate design could meet the fire ratings.

Treated Lumber In Wood Trusses

Question: 

Can one use pressure-treated lumber in metal plate connected truss construction? If so, are special plates or coatings required?

Heat Treated Lumber

Question: 

What does KD-HT mean?

One Hour Roof Ceiling Assembly

Question: 

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?