How high can a wood shear wall be?

[bigalbert6]

I designed some concentic frames to brace a soft-story condition under a two story timber frame structure. Its in seismic zone 4 and the buildings are in danger of falling over in a large seimic event. The frames turned out to be to expensive to build. I'm now re-designing with shear walls, however some of the buildings are 18'-0" off the ground. I can't find an unbraced height limit for shear walls...only the cbc 2:1 height to width ratio. Any one know how high the code allows? Can I frame it with 4x10 to help resist out of plane bulking?

 

[msquared48]

Absolutely. And don't forget the wind / seismic forces normal to the plane of the shearwall - whatever size studs you use, you will have to transfer this normal force to the diaphragms above and below. The deflection lateral the studs will probably control their size.

Remember too, Architects really love 10" wide studwalls.

Mike McCann
McCann Engineering

 

[faromic]

LOL, yeah, good one. They can barely sleep when you tell them you need 2x6's.