A 906 sq ft Woodinville garage with tall walls and a staircase, moisture tested at every step and coated in Lanai Grey flake polyurea in August 2026.
Big garages hide big questions, and the biggest one under any coating is moisture. This Woodinville garage covers 906 square feet, with tall white walls, a staircase up to the house, electrical panels and a long run of wall that the owner wanted coated too. The concrete was sound but marked up, rated Fair, with the usual stains and wear of a working garage.
In August 2026 Cascade installed a garage floor coating in Woodinville with Certified Penntek polyurea in Lanai Grey flake. The way the crew handled the slab's moisture is the part worth reading.
At the free consultation in June 2026, the meter read 4.7%, 5.0% and 5.4% in three spots across the floor. Cascade tests every slab at the consult, because moisture moving up through concrete is one of the main reasons coatings lift.
On install day the numbers were logged again on the Penntek warranty job card:
Slab temperature and dew point matter because coatings need the surface to stay comfortably above the dew point while they cure. Logging them is part of registering the warranty with Penntek.
Prep came first, with the slab ground a couple of days ahead of the coating. Then the crew came back to finish.
When a slab needs it, Cascade uses a two-layer moisture barrier system under the color coats. Moisture testing at the consult is what tells the crew which slabs need it.
Lanai Grey is a soft gray blend with lighter and darker chips. The 1/4 inch flake reads fine-grained from standing height. The wall coating runs well above the slab here, a tall band of flake that protects the drywall from mops, tires and bumped bins. With the white walls and the dark wood stair rail, the room looks finished top to bottom. To compare blends, see our styles and colors page.
The pure polyurea basecoat bonds chemically with the concrete at over 1,300 PSI, helped by a silane adhesion promoter. It is flexible, so it moves with the slab through temperature changes. The Penntek Stretch Test shows that flexibility. The floor carries a limited lifetime warranty backed by Penntek, the manufacturer.
Woodinville sits in a river valley with wet winters, and plenty of local slabs carry more moisture than you would guess from a dry-looking surface. That is why the reading matters more than the look. Our post on Seattle's rainy climate and moisture testing explains it, and how long a garage floor coating lasts in the Pacific Northwest covers what that means over the years. See more of our Woodinville garage floor coating work, or a nearby Woodinville garage in Tidal Wave.
A band of coating above the slab protects the lower wall from mop water, tires and bumped bins, and hides the joint where floor meets wall. On this job 137.5 square feet of wall got the same Lanai Grey flake as the floor.
It is an extra system that goes under the color coats on slabs that need it. Cascade decides based on the moisture testing done at the consultation.
If the slab gets too close to the dew point, moisture can condense on the surface while the coating cures. Logging slab temperature, air temperature, humidity and dew point is part of a careful install.
Curious what your slab reads? Book a free in-home quote or call 425-226-6085. Moisture and hardness testing come with every visit.
Here's just a few of our previous projects.
