High humidity and moisture in the concrete take a little more consideration. Water-based sealers are more sensitive to humidity, which will increase cure time. However, water-based products allow the surface to breathe. “If there is a moisture issue, a solvent-based product is more likely to lose its adhesion versus a water-based product,” Wells says.
Temperature. Sealer manufacturers recommend application between 50 and 90 degrees F. “The sealer needs to be allowed to cure within that temperature range, too,” adds Di Zinno. Anything outside of that temperature range can result in failure. Di Zinno says contractors working in environments on the high end of the temperature scale can do a few things to increase success with a sealer, such as keeping the product in the shade and applying it in the early hours of the day. “Water-based sealers are incredibly user friendly, so I recommend those a lot if a contractor is working in the upper end of those temperature guidelines,” he adds.
Wind. Solvent-based sealers are more susceptible to wind than water-based because wind speeds up solvent flashing.
Salt. Solvent-based sealers tend to hold up better on surfaces that will be exposed to de-icing salts and chemicals better than water-based sealers. Penetrating sealers are a good choice for these environments.
At the end of the day, if you are still unsure, remember you are not alone. Call your sealer manufacturer. They will talk through your client’s desires and your application situation to recommend the best sealer for your project.