Breathable concrete sealers allow the concrete to “breathe”, even after being sealed. So what does this mean? This means that the sealer allows for moisture vapors to pass through the concrete. The sealer may slow down the movement of moisture, but it won’t stop the movement of moisture or trap it below the surface.
Breathable sealers are more than just a choice. In fact, in many cases they are a requirement. Porous surfaces, such as red bricks, need to remain breathable. If a non-breathable sealer is used on a porous surface such as brick, the brick can deteriorate from within the pores, and eventually, the build of moisture will cause the coating to fail.
Breathable sealers are very common for use on exterior surfaces because moisture vapors are constantly mo
ving up through concrete and masonry, even in climates you would consider to be very dry. That is how nature works. Some of the driest climates out West have been known to have some of the worse moisture issues. While precipitation contributes greatly to sub-surface moisture, it isn’t the only source of moisture. Below the surface are water tables and those water tables are constantly expanding. There are many sources of moisture, some seen and others not.
Penetrating sealers are all breathable because they aren’t film forming. Silicate densifiers and silane siloxane water repellent sealers will help to reduce water absorption through the surface, as well as moisture movement up through the concrete, but they will not trap moisture below the surface.
Acrylic sealers are breathable but their breathability will change depending on the solids content of the sealer. 15% and 25% solids acrylic sealers are the most common types of acrylic sealers because of their breathability. 15% solids acrylic sealers are more breathable than 25% solids acrylic sealers, but they both perform well. Once you get up to a 30% solids solution, the breathability dramatically reduces and you can run into issues with delamination and failure.
Best Breathable Sealers by Type of Concrete
| Silicate Sealers | Silane Siloxane Sealers | Acrylic Sealers | |
| Red Clay Brick | X | ||
| Brick Pavers | X | X | |
| Natural Stone | X | ||
| Poured Concrete | X | X | X |
| Stamped Concrete | X | X | |
| Flagstone | X | ||
| Slate | X | ||
| Granite | X |
Want to learn more about the best breathable concrete sealers? View Top Rated Breathable Sealers.
