Materials

Question: 

Where can I find a copy of the criteria used to visually grade lumber?

Question: 

We have a local builder wishing to use floor trusses with a 2-hour assembly. I have shown him the 2-hour design on pages 17-27 of the second edition of SBCA’s Metal Plate Connected Wood Truss Handbook. Is this assembly UL approved? If so, what is the design number?

Question: 

What are the health hazards of black fungus on Douglas-Fir lumber?

Question: 

I am thinking of using wood trusses for the roofing/ceiling structural systems on some houses I shall build. I remember, though, an engineer/volunteer fireman commenting back in 1989 that the connector plates are prone to expand and pop off, early on in a fire, causing catastrophic structural failure. Was this the case, and if so, has this problem been corrected?

Question: 

I am trying to determine the manufacturer of some wood trusses installed in the early 1980s in New Jersey. The stamp mark on the connector plates reads, to the best of my ability, TPL-153A (it could be PPL or TPI, but I am unsure). I need to get in contact with this truss manufacturer in order to determine design loads for the truss, as I am remodeling the store under the roof.

Question: 

What is the life expectancy of wood that was used in an attic truss? Does fire retardant change the life expectancy?

Question: 

I would like to know if there is an age restriction on wood trusses. How long after production are they safe to use? The trusses in question are at least three to four months old. Are they still safe to use? They have not been covered the entire time and are showing signs of age.

Question: 

Can a roof truss penetrate a one-hr. tenant separation wall without having a one-hr. rated ceiling? The building official insists that the 2x4 chords are combustible and nullify the integrity of the one-hr. rated partition that is constructed in an attic above an 8 in. C.M.U. bearing wall. The partition consists of gypsum board attached to 2 x 4 stud framing. The building official insists that a ledger must be attached through the gypsum board to support the trusses each side of the wall. This is almost saying that any rated assembly must have bearing only on other rated assemblies.

Question: 

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

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?