Bracing & Restraint

Installation Guidelines

Question: 

Are there any associations that have recommendations for the installation of wood trusses?

Proper Bracing Of Valley Framing

Question: 

It is critical that permanent top chord bracing is supplied by proper nailing of the valley truss bottom chords to the carrying truss top chords, through purlins or properly installed rated roof sheathing. If the sheathing is not carried through under the valley framing, then the permanent top chord bracing must be supplied in another manner.

Construction Loads On Floor Truss Assemblies

Question: 

How much OSB can be stacked on a floor deck without damaging the trusses?

Gable End Bracing

Question: 

Manufactured gable ends are actually frames even though they are often referred to as trusses. The webs are “studs” oriented vertically and usually spaced at 12, 16 or 24 in. O.C. The gable end frame is designed to transfer vertical loads from the roof to the continuous bearing wall below. Another way gable end frames are different from trusses placed in the interior of the structure is that frames experience perpendicular wind loads. The sheathed frame transfers the wind loads to the roof and ceiling diaphragms and vice versa.

Strongback Bracing

Question: 

I am looking for strongback bracing requirements for a 12 in. deep residential floor system with trusses in lengths up to 19 ft. Can the strongback bracing end at a truss without tying into an end wall? For instance, can three trusses of a type be tied together by strongbacks, then the next series of different trusses be tied together without having to be tied back to the previous type of trusses?

Gable End Bracing

Question: 

Some building designers believe that gable end webs need to be L-braced to 90% of the web length, which sounds fine. However, they spec that scissors gable end webs need to be braced to 100% of the web length. That means that in the field they are notching the braces to fit around top and bottom chords – you can imagine how difficult that can be. Is that necessary or even the intent of the web L-bracing?

Steel Vs Wood Truss Bracing

Question: 

As a forensic engineer who has investigated numerous collapses of wood truss systems, I find your web site an excellent resource on the proper erection of wood trusses. What are your opinions on steel trusses, particularly with regards to installation and bracing? Do you feel that the installation and bracing techniques utilized for wood trusses are applicable to steel trusses? Do you know if that is the general industry standard or are there specific requirements and guidelines for steel trusses? Is there a particular guideline/commentary available for metal trusses?

Warning Poster Caution Notes

Question: 

We are concerned with SBCA’s BCSI-B1 Summary Sheet which under “Notes” makes a disclaimer. Our concern is if there would be an accident with our trusses and we point out that the bracing was not placed correctly according to SBCA documentation, which is sent with every job. If the accident goes to court, how will our attorney respond when the opposing attorney points out the disclaimer, which infers that the bracing we recommend must be flawed, otherwise it would not be disclaimed?

Truss Blow Down

Question: 

If trusses blew down from insufficient temporary bracing and the contractor put them back up without the knowledge of the truss manufacturer and gave the truss manufacturer a letter stating that the trusses were okay, is that sufficient? Do you know of any truss manufacturer who would accept this?

Fall Protection

Question: 

Are wood trusses designed to be fall protection anchors that would support a worker should he fall?