How to Repair Stucco Leaks

by Carson Barrett, Demand Media

Many people find the texture of a stucco wall attractive.

Stucco is a durable, attractive finish used for the exterior walls of homes and other buildings. As with all exterior wall surfaces, the integrity of stucco must be intact in order to prevent leaks. When cracks occur in the stucco and water leaks in, it can reach the sheathing of the house, which can cause rot. You can patch small cracks and holes in the stucco yourself, but if they're larger than 1/2 inch wide or are vertical cracks around windows and doors, call in a professional to examine them, as it can be a sign of problems with your home's foundation.

Patching Cracks in the Stucco

1.

Clean the crack to remove any loose debris with a flathead screwdriver and a toothbrush.

2.

Squeeze caulk into a paper cup and stir some clean sand into the caulk to give it a rougher texture. Use acrylic-latex caulk if the crack is 3/8 inch wide or less, or a stucco-repair caulk if the crack is 1/2 inch wide or less.

3.

Fill the crack with a putty knife and allow it to cure for the time specified on the packaging.

4.

Apply an exterior-grade latex paint over the patch that blends in with the rest of the wall.

Patching Holes in the Stucco

1.

Clean loose stucco from the hole by chipping away at it with a cold chisel and hammer.

2.

Vacuum the dust out of the hole. Examine the wire mesh inside the hole; if it's damaged, staple new mesh over the damaged section.

3.

Mix a small batch of brown stucco for the base coat, following the manufacturer's instructions. Apply the stucco to the hole with a trowel. Allow the stucco to firm up, then scratch the surface with a nail. Allow the stucco to cure for two days. Use enough stucco to reach a depth about 1/4 inch beneath the surface of the wall.

4.

Spray the hole and the stucco that surrounds it to dampen it. Apply another coat of brown stucco to the hole. Smooth the surface of the stucco, and allow it to cure for two days. This layer is 1/8 inch deep.

5.

Spray the hole and the surrounding stucco with water to get it damp. Apply the top coat of stucco over the hole, smoothing the surface so that it's even with the surrounding stucco. Texture the surface of the stucco with the trowel to match the surrounding stucco. Allow the top coat to cure for four days, and paint the patch with an exterior-grade latex paint, if needed.