Moisture moving up through a concrete slab is one of the most common — and most preventable — causes of coating and flooring failure. Here's how to know if your project actually needs a vapor barrier.
Concrete is porous, and moisture from the ground below can migrate up through a slab over time — a process called moisture vapor transmission. A vapor-barrier coating or membrane blocks that migration, protecting whatever coating or flooring sits above the slab.
Moisture testing — using calibrated meters or calcium chloride test kits — measures the actual vapor transmission rate from your slab. This tells us whether a standard coating system is sufficient or whether a higher-rated moisture-mitigating primer is needed before anything else goes down.
Seasonal freeze-thaw cycling can affect how moisture behaves beneath a slab over time, and slab-on-grade construction — common across Colorado — means moisture testing is worth doing before a coating project, not just for problem floors.
Yes — vapor-barrier coatings aren't just for new construction. If you've had a coating or flooring failure that turned out to be moisture-related, a vapor-barrier system can be applied to the existing slab as part of remediation.
The right answer depends on your slab's actual measured vapor transmission, not a generic assumption. Testing first, then matching the system to your real conditions, is what prevents a repeat failure.
Concerned about moisture in a new build or a slab that's failed before? Colorado Polyurea offers moisture testing and vapor-barrier coating services — reach out to schedule.
No obligation. We'll assess your space and give you a real number.