Deflections

[ggss]

need guide lines for differential deflections between floors for high rise bouildings to design curtain walls

 

[daski]

for spandrel beams supporting curtainwall, i try to keep live load delflection to 0.375" or less.



mdaskilewicz@cuh2a.com

 

[phdunn]

IBC 1604.3:
Floors L/360
Roofs supporting brittle materials L/360
Roofs not supporting brittle materials L/240
Other members wind or snow L/240
I have found curtain wall designers do not like this much movement. A 30'-0 span is an inch at L/360, so unless you are in conversations with the structural engineer this is what your limits might be!

 

[rapt]

Ask the curtain wall manufacturer for the limits required for his system.

Then do proper deflection calculations to determine the expected deflections for the edge beams, not the approximate calculation methods in most codes as they are not adequate when you want to know the real numbers.