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What Is The Material Spec For "Lag Screw"?

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Simpson Strong-Tie is now producing and supplying 1/4" dia x (1.5" to 3.5") wood screws, the screws have ICBO ES reports on the capacities.  Fasteners are one area where the industry has failed. 
I have a client who supplies pre-fabricated building components and uses fasteners to attach them, well they are putting these components on California schools which means a DSA (Division of the State Architect) review and the question arises, what are the fastener capacities.
Will I found the IFI references which allowed for capacity determination, then DSA want to know how to check the fasteners to determine that the contractor is supplying the correct items. 
I remember a 60 minutes report about the black market in bolts, in the aircraft industry specific bolts need periodic replacement (like the ones that hold the engines on) and they are very special and very expensive bolts, they found that people had been counterfeiting them and selling them for half price, something like 120ksi bolts to be used and the counterfeit are 36ksi.
So go figure

Williston "Bill" L. Warren, IV - S.E.
Structural Engineering SOLutions
Newport Beach, California
From: "Nels Roselund, SE" <njineer(--nospam--at)>
To: <seaint(--nospam--at)>
Subject: Re: What Is The Material Spec For "Lag Screw"?


I hope you are on the trail of suppliers and specifications for lag screws.
I have not been able to find a way of being sure that the lag screws on a
project conform with my specifications nor to tell a contractor where to
purchase the screws I have specified.  I generally specify the yield
strengths in the footnotes of NDS Table 9.3A, but have never been able to
find out what was delivered to the job.

Nels Roselund
Structural Engineer
South San Gabriel, CA