Connectors & Fasteners

Alternate Nailing Patterns

Question: 

Some truss lumber repair nailing patterns call for 16d common nails. Most nail guns do not support 16d nails, but have an equivalent to a 12/10d nail. Is there a substitution guide or ESR report that could help us?

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?

Bracketless Connections

Question: 

Are there any trusses that are supported strictly by the wood itself without any mechanical connections such as brackets?

Valley Sets

Question: 

What are the requirements for installing valley sets over roof trusses? I am interested in nailing and support conditions. Some engineers ask for the bottom chord of the valley truss to be ripped to match the roof pitch of the underlying trusses. Is this necessary? How can I calculate values for uplift resistance for the building inspector?

Allowable Quality Tolerances

Question: 

What tolerances are allowed for metal plate connectors in wood trusses? How do you take into account the possible presence of splits, waves and knots?

Installing Valley Sets

Question: 

What are the requirements for installing “valley set” overlay roof trusses? I am interested in nailing and support conditions. Some engineers ask for the bottom chord of the valley truss to be ripped to match the roof pitch of the underlying trusses. Is this necessary?

Heavy Timber Connectors

Question: 

I am currently undertaking a project dealing with techniques and methods of joining structural timber members. Do you have any available information on timber connections like split rings and design software?

Liability Issues With Lvl Beams

Question: 

We have been specifying laminated veneer lumber (LVL) beams for some time now. The plans usually state, “Beam to be engineered and supplied by truss manufacturer.” What kind of liability issues do I need to watch out for?

Multi Ply Girders

Question: 

Girders are trusses specially designed to carry extra loads that are a result of the structural framing members they support. Sometimes a single ply girder truss is insufficient to carry the entire load, so the truss designer designs a multiple-ply girder. This is where identical trusses are built and fastened together to act as one unit to support the load. ANSI/TPI 1 states that girder trusses up to three plies thick can be fastened together with nails. Girders over three plies must be pre-drilled and bolted rather than nailed.

Partition Wall Attachment To Bottom Chords

Question: 

I am remodeling a 16-year-old ranch style home. The roof consists of 4/12 26 ft. span trusses, 24 in. O.C., over 2x4 stud walls. What is the recommended means of affixing the top plate of new interior partitions to provide the lateral support needed for the partition? Also, I want to hang a soffit above and overhanging the new kitchen cabinets (recessed lighting placed within). What is the recommended means of attaching the soffit to the underside of the trusses so as not to interfere with the designed movement of the trusses under the variable live load experienced (snow load)?