If you have a little crack in your outside stucco, you can fix it—and you should, or you may end up with more significant repairs later.
Q: My home is 64 years old and still has the original stucco on the outside. There is an okay fracture on one external wall with paint flaking away on both sides. Is there a fast and easy method to repair stucco before the rains arrive, and is it a task I can undertake on my own?
A: Good news: based on your description, it does not seem that your fracture is caused by the foundation sinking. If you had detected wider cracks and symptoms like sticky doors and windows, I would have advised you to contact a foundation consultant. As it is, this is a task that any do-it-yourselfer can do. And it’s a vital job, so you were correct to be cautious. If rainwater gets beneath the stucco, you might be in for a greater issue.
To repair stucco, you may use a variety of commercially available materials. While some are intended to repair deeper gouges and holes, others are expressly intended to repair cracks like the one you describe. Quikrete, for example, makes a sanded (textured) acrylic caulk that is both simple to apply and effective.
The first step can seem counterintuitive: widen the crack to at least a quarter inch using a cold chisel and hammer. The margins of the fracture should be chiseled perpendicular to the wall. If feasible, back-cut the crack, so its base is broader than its top. Then, using a wire brush, remove any loose material from the fracture.
Using a regular caulk gun, apply the stucco repair compound along the crack. As you work, trowel the patch to match the surrounding stucco finish. Give the patch 24 hours to dry before covering it with water-based paint—ideally the same color as the home’s outside.
You may observe that, although having cured, the completed piece is still malleable to the touch. That suppleness attests to the strength of the mending. If the wall moves slightly in the future, the repair will adapt rather than come undone. With the fissure now thoroughly fixed, you can be confident that rain will not be able to penetrate under the stucco.
Keep in mind that you should leave stucco repair to professionals to guarantee perfect sealing and prevent additional damage.