Replies

1. 
   Guest_ | Oct 09, 1999 09:28am | #4

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   I'm designing a shear wall for standard 2x4 frame house (my own house) and cannot find any information on the allowable shear stress I can achieve by using a construction adhesive in addition to 8d nails. The only information I could find included only tables with shear values based on the size of nails, spacing, and sheathing thickness.

   Based on my calculated lateral wind force against the side wall and roof, I have 6000 lbf I need to resist, shared equally by three 2-ft wide walls adjacent to my garage doors. This results in a whopping 1000 lbf/ft of shear! 8d nails @ 3" o/c and 1/2" OSB sheathing will allow 530 lbs/ft. I suppose that if I sheath BOTH sides of the wall, I can double that figure, but I don't feel 100% comfortable with nailing both sides of a framing member every 3" o/c (may result in splitting the stud.) Thus, I would like to know if adhesive will help me out and by exactly how much?

1. 
   Guest_ | Oct 08, 1999 01:28am | #1

   *Chris,Although I can't relate to your figures, ( we use Kilonewtons per meter here ) achieving satisfactory bracing in those small panels is always a problem.One way to beat it is to install a ceiling diaphragm and transfer those forces to other walls. A diaphragm can be as simple as to crossed metal straps at the ceiling plane, or as complicated as fully sheathing the ceiling.mark

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   Guest_ | Oct 08, 1999 05:16am | #2

   *Chris,If the panels have a width any less than 1/3.5 times the ht then torsional effects come in and it won't resist the shear anymore. Unless the wall is only 7' tall the 2' width won't work. This is why 2'8" is the minimum width for panels per UBC (for a typical 9ft garage wall). Another item though is the moment which would have to be resisted by hold downs. Even if the wall WERE only 7ft tall, each hold-down would have to be rated at 7,000lb, given the 6,000lb force you mentioned. DH

1. 
   Guest_ | Oct 08, 1999 07:20am | #3

   *On the adhesives, my understanding is that they're inappropriate for shear because they "creep"? Come to think of it, I haven't really heard of them being used for truly structural purposes, rather as method of locking members together more tightly without increased strength. (?)

1. 
   Drew_Kirk | Oct 09, 1999 09:28am | #5

   *Chris, check out the 1999 Simpson StrongTie catalog. Their StrongWall products provide massive shear strength, designed for such installation as yours. If you get the chance, attend their seminar.