Brick has been used in residential construction for centuries, and it’s not hard to understand why. It’s simple, attractive, and durable. Yet it’s also associated with some of the most troublesome repair jobs I see in my work as a consulting forensic architect in Nashville, Tenn.
In this article, I’ll focus on standard residential brick veneer — that is, nonstructural brick installed as a cladding over wood framing — and share examples of some of the failures I’ve inspected. Sadly, I see the same mistakes made again and again — mistakes that often result in very expensive callbacks.
Take the house whose repairs we cover in the slideshows. The owners reported recurring leaks and damage to pricey custom finishes inside. By the time I was called in, they were understandably upset at the many failed attempts to fix the problem. Typically in a case like this, the “repair” consists of applying tubes of caulk or mastic around windows and flashings — inevitably a waste of time. As you can see from the photo, getting to the root of this house’s problem was a little more involved than that.
So how can a material so durable go so wrong? Simple: It doesn’t. As with any building material, successful installation depends on workmanship and details — rarely does the brick itself fail. Laying up a flat wall with straight, even courses and raking the mortar joints is the easy part; the challenge is making sure that the brick is supported properly, that it’s securely tied to the structural wall sheathing, and that adequate measures have been taken to ensure that moisture that gets behind the brick can exit to the outside.
Where Does the Water Come From?
Brick is made from clay and fired at high temperatures. Naturally, that makes it water-resistant, right? Generally, yes — especially modern brick. (Older bricks are more porous, and will absorb a surprising amount of water.) But that doesn’t mean a brick veneer wall is waterproof. One culprit is the joints. Mortar is made by mixing water, sand, and cement. That alone introduces tiny air bubbles. And once it’s troweled on and the water in the mix evaporates, you have even more holes, as well as lots of hairline cracks that form between bricks. Wind-driven rain will soak the wall, and as the moisture moves from wet to dry and warmer to cooler, the back of the brick will eventually get wet — you can count on it.
Plus there are all the other common leak spots — like roof and wall penetrations, and (of course) windows.
