I am the Executive Director of a senior housing community in Portland, OR. One of our buildings is brick with a cement foundation/basement (partially above ground, partially below). We want to seal the brick and cement against moisture with siloxane or something similar, and are considering painting the cement with an elastomeric paint over the sealant.
However, we’ve been told that elastomeric paint will wick moisture up from the ground, and ultimately bubble and peel. In fact, our contractor says he won’t warranty the job if we use elastomeric. What’s your take? Should we use the elastomeric, or just a high quality exterior latex?
I've never heard of elastomeric paint wicking moisture from the ground. What can is the concrete foundation. If it is unsealed below ground level, then it is possible that some moisture could migrate to the area that is painted. This could cause problems.
Using the sealer you mentioned under any paint will cause adhesion problems. The sealer will need priming and even this could be a problem. It is best to prime with a very good masonry primer then paint and not use the sealer.
If you have noticed that the foundation is very wet above ground for extended periods of time consider just using the sealer without painting. Some silicone concrete sealers are available in different colors, like sealing and staining at the same time. This would be a good alternative to painting your foundation.
