Painting exterior stucco is a good option for some homeowners. Most stucco is made of Portland Cement, sand, and lime. It is said to have a lifespan of 50-80 years which makes it very desirable when looking for a durable finish. However, over time exterior stucco can develop fading, staining, and hairline cracks. If deep cracks are discovered, it’s best to contact a stucco repair company to repair the crack. This will help to avoid any chance of moisture damage.
Hairline Cracks
Fading, Hairline cracks, and staining can be dealt with by painting stucco. Hairline cracks, between 1-5 millimeters, are usually not a concern. These cracks tend to be on the surface, but not in the wall itself. Painting stucco can cover over the hairline cracks and staining at a much lower price point than stucco resurfacing. Therefore, painting exterior stucco tends to be the choice for many.
Stucco is a masonry coating and therefore needs to allow water vapor to escape. After stucco is applied it tends to have a high pH. During the 30-90 day curing process the pH will drop. Before applying any type of coating it is recommended that you wait until the stucco has fully cured and the pH has dropped between 6-9. Using a pH neutralizer or alkali-resistant primer may be beneficial when waiting is not an option, . Make sure the product you plan to use says it can be applied to stucco.
Use A Flat Sheen
We recommend using a flat sheen on stucco. There are stucco specific products on the market and most are only offered in a flat sheen. This is because the stucco surface is naturally inconsistent. A glossy sheen will highlight those inconsistencies, which can give a blotchy undesirable finish. If the application of the stucco is consistent, a more glossy sheen can be used. However, it is often difficult to tell how consistent the texture of the stucco is until after the paint has been applied. We therefore do not recommend anything but flat.
Elastomeric Coating
Some of the masonry products available are marketed as an elastomeric coating. Oftentimes these products are thicker than typical paint. They contain not only acrylic, but other polymers that are “elastomeric”. There is some debate on what climates an elasomeric paint will perform well in. Some will argue that you should avoid these products in drier climates. While we are uncertain on this debate, a high quality product from a reputable source should produce a great result either way.
Oil-Based Paints
Usually stucco is one of the last places we see paint failures on homes. Oil-based paints should be avoided when it comes to painting stucco. They do not “breathe” like a water-based coating will.
Preparing Stucco For Paint
Preparing the stucco for paint will require a good power washing. It is critical to remove dirt, loose paint, and efflorescence. Efflorescense is a crusty white salt deposit that can appear on stucco, concrete, brick, and other masonry surfaces. If not properly removed before repainting, these can cause adhesion problems when painting stucco.
If the hairline cracks in your stucco are small enough, paint is your best option for a uniform finish. However, if the cracks are too large for paint to fill in and you are not going to have them repaired with stucco, you will want to fill that void with an appropriate caulking material. These filled cracks will be noticeable after painting because the texture of the filled cracks will be different than the texture of the surrounding stucco. Using a flat sheen product will help hide this inconsistent surface.
Painting exterior stucco is a great choice for those homeowners who are unhappy with the cosmetic issues of hairline cracks, fading, or staining, or who simply want a change of color. Painting stucco is about 1/10th the cost of resurfacing and can achieve the end result many are looking for.
