Veneer Expansion
Veneer Expansion
(OP)
How do you figure out how much expansion you will get from a masonry veneer?
I would suspect that you would calculate the moisture expansion using the coefficient of moisture expansion for clay masonry and add that to the calculated thermal expansion using coefficient of thermal expansion for clay masonry.
Therefore, for a 25' tall veneer wall in an area with a 50 degree temperature swing you would get 25*12*3*10^-4+25*12*50*4*10^-6 = 0.15 inches.
Is this correct?
I would suspect that you would calculate the moisture expansion using the coefficient of moisture expansion for clay masonry and add that to the calculated thermal expansion using coefficient of thermal expansion for clay masonry.
Therefore, for a 25' tall veneer wall in an area with a 50 degree temperature swing you would get 25*12*3*10^-4+25*12*50*4*10^-6 = 0.15 inches.
Is this correct?






RE: Veneer Expansion
RE: Veneer Expansion
See http://www
RE: Veneer Expansion
So temperature expansion is independent of moisture? If I'm in an area that is subjected to 50 degree mean temp fluctuations I would not add the thermal expansion together with the moisture expansion to figure out the maximum movement of the wall?
RE: Veneer Expansion
If you have low floor to floor heights (9' or 10'), I would support at every other floor; high floor to floors (12' or more), support at each level. In low rise buildings, support at every floor, in high rises look much more closely at alternate floors, if feasible.
Make sure your details can accomodate that amount of growth.
RE: Veneer Expansion
RE: Veneer Expansion
However, is it true that you do not add the thermal expansion number with the moisture expansion number?
RE: Veneer Expansion
RE: Veneer Expansion
I use 3x10^-4 in/in for brick moisture expansion.
I use 6x10^-4 in/in for creep and shrinkage of the concrete.
*100 degree F temp change
So for an insulated concrete frame with face brick, 12 feet floor to floor the total is
(6+3+6)x10^-4 x 144 inches = 0.22 inches or 1/4" minimum joint.
Check out BIA tech note 18 series.
RE: Veneer Expansion
BA
RE: Veneer Expansion
Clay brick has a long term expansion that can vary from manufacturer/clay type. Concrete masonry units have a long term shrinkage that is markedly high early and decreases to almost zero.
Dick
Engineer and international traveler interested in construction techniques, problems and proper design.
RE: Veneer Expansion
http://www.gobrick.com/html/frmset_thnt.htm
RE: Veneer Expansion
According to the technical documents, you can get up to 1/8" brick expansion in a 12'-0" floor to floor height. Then supporting the brick at every other floor would produce ¼" of brick expansion which would have to be accommodated in the architectural details (I would think this would be very hard given a typical mortar joint is 3/8" leaving no room for a supporting angle).
However, the prescriptive requirements allow you to go the first 30' without any support and then you need to provide support at every floor after. This would require (30/12)*.125 = 5/16" of expansion at the support location which would need to be detailed into the joint. This leaves no room for a supporting angle (unless you cut out the back of the brick).
How is it possible that they allow you to go the first 30' without a joint when expansion is such a problem?
RE: Veneer Expansion