Masonry Expansion/Contraction Joints
Masonry Expansion/Contraction Joints
(OP)
Is it necessary to have Expansion/Contraction joints in CMU backup block walls in a Composite Wall construction? (Brick Veneer and Backup Block)
In other words: if the CMU is not exposed to weather and is an "interior" item, are vertical joints still necessary?
I couldn't find a code section that addresses that clearly.
Thanks!
In other words: if the CMU is not exposed to weather and is an "interior" item, are vertical joints still necessary?
I couldn't find a code section that addresses that clearly.
Thanks!






RE: Masonry Expansion/Contraction Joints
RE: Masonry Expansion/Contraction Joints
Attached is a fairly old document - shows spacing recommendations for interior and exterior conditions.
The MIA Masonry Engineering Handbook recommends a spacing of 25 ft. or a maximum length/height ratio of 1 1/2 whichever is smaller....independent on whether the wall is interior or exterior.
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RE: Masonry Expansion/Contraction Joints
Dave
Thaidavid
RE: Masonry Expansion/Contraction Joints
If you use an "eye and pintel" system, the exterior wythe sees different conditions than the interior (temperature/moisture) and can perform well. The ties allow the differential lateral movement of the wythes. Joint reinforcement with diagonal elements and welded brick ties acts differently.
Dick
Engineer and international traveler interested in construction techniques, problems and proper design.
RE: Masonry Expansion/Contraction Joints
Sorry for the late response - I was away during holidays!
RE: Masonry Expansion/Contraction Joints
RE: Masonry Expansion/Contraction Joints
I espouse the idea that you can increase the length between joints if you have joint reinforcement.