Go to the publications area of our website (www.apawood.org) and search for “TT-070”. We publish ultimate nail head pull through results for 8d common nails. Obviously these values are ultimate, a suitable factor of safety should be applied! I think you’ll find that nail withdrawal from the framing will be the more common limit state.
Tom
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Thomas D. Skaggs, Ph.D., P.E.
Manager, Product Evaluation
Technical Services Division
APA - The Engineered Wood Association
7011 S. 19th Street
Tacoma, WA 98466
ph: 253/565-6600
fx: 253/620-7235
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From: jerold taylor [mailto:jerold_taylor@yahoo.com]
Sent: Wednesday, December 12, 2007 08:45
To: seaint@seaint.org
Subject: Uplift on Roof Sheathing - "Pull Through" Resistance
I would like to ask for feedback on the design / specifying of sheathing for uplift.
For uplift on roof sheathing in HIGH WIND areas, is “Pull-through” a concern for the Plywood or OSB? For Component and Cladding loading at some of the end zones, net uplifts can exceed 100 psf (for example, ASCE 7-02, V=130 mph, Exp. C, Bldg Class. III and Zone 3).
APA provides design data for allowable stresses for spans and thicknesses of material, but for a situation where loading can be concentrated at the nail head “bearing” (kind of a reverse punching shear), are there special precautions I should warrant against? Are there some type of washer that is sometimes typically used at these locations to help “spread out” the load?
I have tried to find specific info on the Internet, without success, so I was hoping for some assistance from those who work with such high uplift pressures more frequently than I.
Thanks
Jerold Taylor PE
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