I use FS of 6 times the load duration factor which comes out close to 4. This is based on the APA technical note for "Fastener Loads for Plywood - Screws Number E830C, December 1995". Tested values for OSB should have a similar factor of safety.
Jared
From: Drew Morris <dmorris@bbfm.com>
To: SEAINT <seaint@seaint.org>
Subject: Safety factors for attaching screws to OSB
I have it in my mind that the recommended safety factor for screws in
withdrawal from OSB is a minimum of 4. Does anyone know what APA
publication lists this? I have been searching the publications that I
have and cannot find it. I have a call into APA.
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