Ask the Architect

Do we take all the brick down?

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Q. We renovated in 2005, and the new kitchen/breakfast room got brick that was a good match with the rest of the house. Now, however, the brick has long cracks running up and down near the corners and white, chalky stains everywhere, and some cement between the brick has come loose. The rest of the house has the same thing, though we didn’t really notice it as much until this happened. We got estimates, and some brick people want to take all the brick down and start over. This seems extreme. What can we do to avoid this?

A. Move. What you described is too common in residential construction. I rarely see similar conditions in commercial work, mainly because commercial projects have technically trained bricklayers and management that know how to properly install the “system.”

That’s right, like every part of any building, brick construction is a system. For decades I’ve observed residential brickwork placed incorrectly, right against the exterior wall, with no air space. The problem is that placing brick right against waterproofed walls traps moisture, in the form of vapor, liquid or solid (when ice crystals form). Trapped moisture is part of what you are seeing.

The other problems are caused by not providing a way for the moisture to naturally get out or for the whole wall to move without pushing against itself like a logjam trying to relieve pressure. The choked wall is pushing moisture, and lime or calcium from the mortar, out through joints, which is what that chalky substance is. Every material is subject to water and movement, whether inside or outside the building. Inside it’s mostly humidity that works on materials, unless you have leaking.

Your home must be assessed to see what can best relieve the problem. In some cases, vertical joints can be created within 12 to 18 inches of the wall corners, with a silicone or flexible backer-rod inserted into the new joint, but this should be done only by a trained professional, not the caliber of company that installed the brick without accounting for expansion or water flow. Special “weep holes” may be added to the brick wall base, in mortar joints 16 to 24 inches apart, with no guarantee that the water getting into the wall will run out of these new relief ports, mainly because there is no space behind the brick.

A correctly built brick wall has a 1½- to 2-inch clear air space behind the brick, which requires a correctly sized, planned width of the foundation wall below before the work is done, and “wall ties,” which are L-shaped straps that attach to the wall and are bent into the brick joints and mortared into place as the brick wall goes up. Without them, the wall could expand when ice forms inside the joints, causing a collapse. It might sound complicated as a system, but each part is important. You may need some reconstruction, or you might want to move. Good luck!

© 2019 Monte Leeper. Readers are encouraged to send questions to yourhousedr@aol.com, with “Herald question” in the subject line, or to Herald Homes, 2 Endo Blvd., Garden City, NY 11530, Attn: Monte Leeper, architect.