IBC table 2306.3 - shear wall question 1

[SLTA]

In IBC-09 Table 2306.3, allowable shear for wood structural panel shear walls etc:

If I call for plywood nailed appropriately on both sides of the wall, can I double the values in the table for my allowable shear?

 

[JAE]

I think it says that in the footnotes doesn't it? Or check the actual code section that references this table.
Typically you can double capacity in shear by sheathing both sides.

 

[SLTA]

JAE, I checked both of those first and there is no clear answer. Thanks.

 

[kylesito]

Yes, you can. In the 2008 SDPWS this is stated in section 4.3.3.3. As long as the grades, nailing, etc are the same then the capacities can be doubled. If the grades, nailing, etc are different, you can only double the lower value. Make sure you take into account the wind reductions though in the table the same for both sides.



PE, SE
Eastern United States

"If a builder builds a house for someone, and does not construct it properly, and the house which he built falls in and kills its owner, then that builder shall be put to death!"
~Code of Hammurabi

 

[XR250]

also, make sure you can actually get the load into and out of the shearwall...

 

[msquared48]

slta: Yres you can, but you have to have the same nailing pattern on both sides of the wall, and may have to stagger the panels if I remember correctly.

Mike McCann
MMC Engineering

 

[AELLC]

From my structural notes:

Note A: Where P2, P3, P4, or P5 panels are applied on both sides of wall, use Note B. For P2 and P3 panels on both

sides of wall, panel edges may be offset to occur on different studs in lieu of using ( 2 ) - 2 x studs per Note B.

Note B: The following items are required, at Contractors' option: ( In lieu of 3 x studs )

Stagger panel fasteners between top plates of stud wall and face nail top plates w/ 10d nails at 4" o.c

Provide ( 2 ) - 2 x studs at panel edges w/ panel fasteners staggered and face nail studs w/ 10d nails at 8" o.c

P1 is 3/8" WSP w/ 8d @ 6", P2 is 8d @ 4", etc.
P5 is 1/2" WSP w/ 10d @ 2"

So when you have P2 to P5 both sides, you need 3 x sill plate and 3 x studs unless you provide Note B.
If you have P2 or P3 you can stagger panel edges to avoid using 3 x (or double 2 x)

 

[AELLC]

Correction to above - add to Note: B

Provide (2) - 2 x sill plate with 10d nails at 4" oc face nailed

 

[SLTA]

Excel, thanks for the reminder - that part I have covered. Thanks, folks!