Why Are Waterproof Paints Bad for Basement Walls?

When it comes to moisture problems in a basement, there are few solutions out there that have been proven to work. Waterproof paints are not one of them. Despite their popularity, waterproof paints are used, not because of their effectiveness, but because it is a cheap solution that requires no professional installation. The problem with waterproof paints is that they are only semi-effective at blocking water vapor and moisture for around two years. After that, they completely deteriorate to the point where the coat of paint may as well not be there at all.

Waterproof paints aren’t thick enough to completely stop moisture seepage. As the moisture permeates through the concrete and reaches the thin layer of paint, it raises the paint and causes bubbles to form along the surface of the concrete. After the paint disintegrates, you can’t even paint over the wall again since most waterproof paints advise not painting over walls that already have a layer of paint on them. So, not only is it a short-lived solution, you can’t use it again after the first time. If you do paint over the old layer, it will be even less effective than before and your basement will remain humid.

A superior waterproofing solution to waterproof paints would be a vapor barrier. Vapor barriers are made of thick polyethylene and are mechanically applied to the walls, so they never fall off. They are durable, anti-piercing, and extremely tough, so they never tear or flake off, even after years of exposure to moisture. If you want a job well done, vapor barriers do require professional installation, but don’t let this discourage you from using it for your basement. Because it’s a one-time investment, you’ll be saving up money in the long run, as opposed to the constant painting that some homeowners put themselves through because they choose waterproof paints.