Concrete sealer turns white or peels in Schenectady, NY for one of two reasons. Moisture got trapped between the slab and the sealer, or sealer was applied too thick or over an old coat that had not worn off. Both show up as cloudy white patches, blisters or flakes, and both need the old sealer stripped before anything new goes on.
Trapped moisture
Solvent based sealers need a dry slab. If the concrete was sealed a day after rain, or the ground under it stays wet, water vapor pushes up through the slab and gets stuck under the sealer. That is the milky white haze you see on patios in Niskayuna and Rotterdam after a wet spring. Sometimes a solvent wash releases it. Often it needs a full strip.
Too much sealer
Sealer is meant to go on thin. Every extra coat on top of an old one builds a film that cannot breathe, and that film eventually lets go in sheets. We see this most on stamped concrete that a homeowner has sealed every spring with a big box store product. The fix is the same, strip it back to the concrete and start over with one proper coat.
How a strip and reseal works
- Apply a chemical stripper and let it work.
- Pressure wash the softened sealer off the surface and out of the stamp lines.
- Let the slab dry completely, usually two dry days.
- Re-tint faded color if needed, then apply one thin coat of fresh sealer.
Do not put another coat over white or peeling sealer. It seals the problem in and makes the strip harder later.
Edges Unlimited strips and reseals stamped and plain concrete in Schenectady, Clifton Park and across the Capital District. Request a free quote and we will tell you whether a wash or a strip is the right call.
