Video Proceedings
To view the presentations, please
Sign In or Register
HOME | About SSPC 2018 | | Contact

The Definition and Cause of Osmotic Blistering in Resinous Floor Coatings


By Marcus Gray, Dur-A-Flex

Presented at SSPC 2015; Session: Concrete Floor Protection; Session chair: Bob Murphy, The Sherwin-Williams Company

You must sign in to view this presentation.*

*By signing in and accessing the video, you agree to the terms and conditions of this site.

Understanding the key components that cause osmotic blistering is essential to not only applying the proper concrete floor coating, but for potentially walking away from a problem floor. Resinous floor coatings are organic coatings that have limitations. Coating failures are typically linked to moisture in the concrete slab. This can be a problem for resinous floor coatings that aren't moisture tolerant. However, there are cases when moisture tolerant coatings fail. The combination of the concrete surface (semi-permeable membrane), moisture, soluble salts/ions, and non-breathable coatings creates the osmotic cell with pressures that can exceed the adhesion strength of the coating. When the pressure exceeds the adhesion strength, blisters will occur.

Concrete has natural levels of Sodium (Na+), Potassium (K+) and Chloride (Cl-). These ions are typically found in sand, gravel, and Portland cement, which make up a concrete slab. Additionally, they can be found in the soil. Elevated levels of these soluble ions and/or salts at the bond line can have a destructive effect on the bond between the resinous coating and concrete.

© 2012-2023 SSPC. All rights reserved. | Terms of Use | Privacy Policy

Phone: 412.281.2331 | Toll-free: 877.281.7772 | Fax: 412.281.9992 | |