Stucco repair is an economical and aesthetic option for fixing the exterior of one’s house. It is mostly a combination of sand, water, lime, cement and a few other ingredients that the manufactures might add for certain purposes. When stucco is used over wooden surfaces, there are more logistical difficulties compared to when it is applied onto a block house which is an easier process, since block is relatively more stable than wood.
Step 1: Traditional Versus Modern Stucco
Traditional stucco is heavier and more durable compared to modern stucco. Although traditional stucco is more solid, modern stucco requires two coatings whereas traditional requires three. The prime way of identifying one from the other is that in modern stucco, lime is replaced by Portland cement. Other ingredients (sand & water) are present in both.
Step 2: Assessing the Damage
Spot areas with missing stucco layers, cracks, bulging or soft surfaces with hollow sounds. These are the areas you will be repairing.
Step 3: Preparing the Stucco
Follow the manufacturer’s instructions for preparing your stucco optimally. If you are preparing it yourself, mix four parts Portland cement, one part clean Sand and water in a bucket. Add enough water for making it into a thick paste rather than a runny liquid. Do not mix for more than 15 minutes. Also, prepare only so much stucco that it does not dry up inside the bucket since that way it becomes unusable.
Step 4: Preparing the Area
Chisel out old stucco from between the blocks so that the new layer can be applied smoothly. Use a screw-driver or a hand-held chisel and a hammer for the job.Wear eye-protection. Use a sponge to thoroughly dampen the area that needs to be repaired so that it doesn’t suck the moisture out of the new stucco. Apply PVA onto the block surface so that the stucco can stick to the surface with ease.
Step 5: Layer One
Before the PVA dries out, apply the first layer of stucco with a trowel. Let the thickness of this layer be approximately 10 mm. Make sure the stucco is applied evenly onto the entire surface. Cover the gaps between the blocks with the stucco too. After 2 hours, scratch the coat with a plaster’s rake. The scratched lines should not be more than 1/8 inch deep. Use the rake to form lines perpendicular to these ones and form a crisscross pattern. Allow this layer to dry for 3 to 4 days.
Step 6: Layer Two
When working with traditional stucco, repeat layer one and then move on to this step. For modern stucco, let this be the final coat. Remember to keep the surface as moist as possible since a prolonged drying process means a more durable coating. If the finish needs to be colored, add coloring dye to the stucco now. Use the trowel to apply the final coat and let this layer smooth the surface by blending into the existing stucco. The eventual thickness of the stucco should be 1 inch. Allow it to cure for at least 3 weeks before applying paint onto the wall.