Deflection of Reinf. Masonry Wall backing up brick 5

[jechols]

I am currently designing a 32'-0" tall, 12" block wall supporting long span roof joists. I have determined for my loading conditions that #5 at 24" o.c. is adequate for strentgh. When I presented this to the boss he thought deflection might be a problem since the wall is backing up brick. I usually do not perform a deflection check for out-of-plane loading on a masonry wall (IBC 2003/ASD). I have determined the theoretical defl. to be about 1.5" and L/600 equals 0.64". Any thoughts? To meet the L/600 I would have to grout the wall solid.

Add'l info:
DL 1650 plf
LL 1100 plf
wind 16 psf
sds 0.32
6' parapet

Thanks in advance for your comments!

 

[DaveAtkins]

I have said this on other posts, and I realize that I am in the minority, but...brick is flexible out of plane, and so when I design wood stud backup, or steel stud backup, or CMU backup, I use L/360 deflection. I have an article regarding testing done at Clemson that backs up this deflection limit.

DaveAtkins