Table of Contents:
Small, perfectly round circles have popped up on the surface of your freshly applied epoxy coat. Fear not, as this issue is actually a very common byproduct of an effect called “outgassing.”
And while this surface anomaly may take away from your floor’s aesthetics at first, it does not affect the integrity of the coating itself.
Outgassing in epoxy floors can create pinholes and bubbles.
Outgassing occurs when trapped air or gases inside the concrete are released. This condition is temporary and typically happens during installation, unlike the more serious issue of moisture vapor transmission (MVT), as we’ve covered in a previous blog series.
Outgassing produces two distinctive faults: small blisters, referred to as “pinholes,” which leave a small, round crater in the coating after popping or the release of gas.
The other is bubbles that emerge out of the coating.
As an epoxy floor sets and outgassing occurs, bubbles rise to the surface and can trap liquids and dirt.
Bubbling can also happen if the concrete itself has air trapped inside. When pouring an epoxy floor, the air might then escape from the concrete and cause bubbles on the surface. The outgassing can occur from changes in conditions in the space, as well.
Pinholes can be small in size, as seen here in comparison to a penny.
There are several methods professionals employ in removing bubbles from epoxy floors. They include:
It’s important to remember that while epoxy bubbles and craters may be an unattractive sight, they do not affect the bond strength of the coating. And while installers have a few tricks up their sleeves to tame outgassing bubbles, always seek out professionals who take the time to conduct proper preparation and avoid issues from the beginning of an installation.
Stonhard is the unprecedented world leader in manufacturing and installing high-performance polymer floor, wall and lining systems. Stonhard maintains 300 territory managers and 200 application teams worldwide who will work with you on design specification, project management, final walk-through and service after the sale. Stonhard’s single-source warranty covers both products and installation. Contact us to learn more about our precision installation methods and specialized products.
Subscribe to upcoming topics!
©2025 STONHARD. ALL RIGHTS RESERVED