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Q.I'd like to finish the above-grade portion of a poured-concrete foundation with a color coat of stucco. The broken-off snap-ties are visible and are slightly rusty. Do I need to treat these with anything before I apply the stucco to prevent a rust stain on the finished surface?

A.Jay Meunier responds: Ideally, the snap-ties should be broken back so that the ends are 1 to 1 1/2 inches from the surface of the concrete. Then the holes around the snap-ties should be plugged with hydraulic cement to prevent moisture from entering through capillary action. This should prevent rust from bleeding through and staining the stucco coat.

It sounds in your case like the concrete contractor used the kind of snap-ties that are designed to break off at the surface of the concrete. These are fine if the intention is to cover the foundation wall with a drain board or foam insulation system. But there are also special ties available that will break off below the surface. Next time you plan to stucco a wall, let your foundation contractor know in advance, and he can use those.

I've been in your situation a couple of times. Once, I drove a piece of 1/4-inch tubing as far over the ties as possible and used it to rock the ties back and forth until they snapped off below the surface of the wall. Another time, I used a grinder to take them down. This also removed some of the concrete around the tie, but the hydraulic cement patched that. Fortunately, you usually have to stucco-coat only a narrow band of wall that's exposed above grade, so you won't have to treat every tie in the wall. Good luck.

Jay Meunier was formerly owner and operator of a residential concrete business. He is now an estimator for Pizzagalli Construction in Burlington, Vt.