Building Component Safety Information (BCSI)

Responsibility For Multi Ply Girder Truss Assembly

Question: 

I am reviewing a truss package that includes multi-ply trusses. Where do I find the requirements for the attachment of the individual trusses to each other (nails and/or bolts)? Is this a requirement that the structural engineer of record needs to supply or is it the responsibility of the truss manufacturer to design?

Trusses Exposed To The Elements

Question: 

We are having a house built and on a recent visit we brought along a friend who builds houses for a living. He noticed that the trusses were wet and a bit moldy. The wood seemed warped, brown, and had white splotches on it. We are worried that it would later make the roof uneven. How could we tell how long the trusses have been exposed to the elements? What options do we have from here? Do we request new trusses, or can these be repaired?

Industry Standard Responsibilities

Question: 

What is the industry standard for ordering residential roof truss systems: Should the general contractor/builder field measure before ordering trusses or should he rely on the blueprint? Who is responsible for their accuracy – the plan service, the truss manufacturer, the builder/general contractor or the framing contractor?

Gable End Bracing

Question: 

Is there a detailed table for gable studs that gives the maximum length a vertical member can be before a lateral brace is required?

Installation Guidelines

Question: 

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

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.

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.

Sealed Placement Plans

Question: 

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

Submittal Packages and Jobsite Packages: What Should Be Included?

In order to promote the safe installation of building components including trusses, manufacturers send out a Jobsite Package to the construction site with the truss delivery. These Jobsite Packages include the Truss Submittal Package. The Truss Submittal Package includes the information that if required will be submitted to the Contractor/Building Designer, who if required will submit it to the local building official.

Planning Ahead: What Issues Should SBCRI Explore?

The Industry Testing Subcommittee is making plans to keep SBCRI busy in the coming year.