Non-Residential Codes (IBC)

Truss Bracing At Supports

Question: 

I almost always see wood trusses erected with no stability bracing at points of support. It seems to me that common sense and section 3.3.3.4 of The American Wood Council’s National Design Specification for Wood Construction (NDS) require that lateral support be provided at points of bearing. Plywood decking doesn't provide any more restraint for a wood truss than it does for a roof joist. I doubt if it was a concern with short span trusses having 4 in.

Truss Attachment Information

Question: 

Would you please inform me of the specified requirements of the size and the amount of nail attachments from the truss to the top plate?

Ga Rc 2601

Question: 

In RC 2601, is RC-1 Channel used?

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?

Fire Damage Assessment

Question: 

How do you evaluate whether a metal plate connected truss is still usable after exposure to fire? Are there any recommended tests?

Attachment Of Scissors Trusses

Question: 

What is the correct method of attaching scissors trusses to the top plate? I read recently in a trade magazine that this type of truss should be toe-nailed on one end and attached with slotted clips on the other end. According to the article, this is to allow for movement of the truss. We require PE stamped spec sheets from the truss manufacturer to verify trusses meet wind and snow loads. These sheets give bracing requirements but never give recommended attachment requirements.

Snow Load

Question: 

I am a truss manufacturer in an area of the country that often has some pretty severe winters. It concerns me how little some of the local builders seem to know about snow load design. What are some of the things that need to be considered?

Design Responsibilities

Question: 

My company supplied roof trusses for a hotel project. The building inspector shut the project down because the trusses were not designed to account for additional snowdrift loading. The construction plans did not contain any snowdrift loading information. The architect is claiming it is our responsibility to determine drift loading, therefore we must fix the problem. Do you have any documentation to help us dispute the architect’s claim?

One Hour Fire Rated Assemblies

Question: 

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.

Sealed Placement Plans

Question: 

Is it the responsibility of the truss manufacturer to provide a sealed layout drawing for roof trusses?