drift limits with storefront

[bjb]

I'm working on a building that uses aluminum store front for cladding-lots of glass. In between the store front sections is metal stud framing. The top of the storefront framing is about +9'-4" AFF, and the top of the curtain wall is about +18' AFF. We basically have modules of storefront that are getting inserted into metal stud framing.

How much drift is acceptable at the top of the storefront? I seem to remember a value of about 1/2" in a 10 year wind. Thanks.

 

[UcfSE]

I would use something on the order of H/400 for 10-year wind. If your studs are curtain walls only, non-bearing and not LFRS, you can also look into using deflection clips that allow slip for drift as well as vertical deflection. Then no drift reaches your storefront.