- 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.