Stucco is the common name for cementitous Plaster and is the plaster product that is applied on the exterior of homes.
It is made from cement materials, sand and water. This is all mixed together to create a slurry. This slurry is applied over a metal lath that allows the stucco to adhere and maintain its strength. However, it can also be applied over concrete, cinder block, clay brick, adobe or even straw bales.
Stucco is a low-cost finish that is strong and durable, and is usable in most climates. It is fire resistant, can have any color added to it, and allows for a variety of textures.
Just a small sample of textures available in stucco.
Stucco is usually done in a 3-coat system. Similar to Plaster, which was discussed before, these steps consists of a scratch coat, brown coat, and finish coat. When applied by hand it is done with a hawk and trowel.
The scratch coat is applied first to provide a strong base for the system. It’s embedded in metal lath, which strengthens and secures the coat. The brown coat is applied next to create an even surface for the finish coat. The finish coat is applied last, creating the decorative finish on the wall surface.
Stucco can also be applied via a pneumatic system. This involves a trained person on a sprayer. After the person with the sprayer moves on, a crew with trowels smooth out the stucco and ensure it is pushed into the lath.
While it looks like a simple project to apply stucco, it is more difficult than it appears. The mis-application can lead to cracking, bulging, separating and moisture intrusion, so it is best to leave stucco application to professionals such as RFJ Meiswinkel.