What a coating actually does
A fluid-applied coating is rolled or sprayed over an existing roof membrane to form a new, continuous, waterproof layer. Done properly it seals minor seam gaps, restores the reflective surface, and protects the membrane underneath from further UV breakdown.
On the Front Range, UV is the quiet killer of flat roofs. At Broomfield's elevation the sun is harsher than at sea level, and a chalked, brittle membrane is common by year fifteen. A reflective white coating brings the surface temperature down and slows that aging considerably.
Silicone versus acrylic
Silicone coatings tolerate ponding water, which makes them the safer choice on roofs where drainage is imperfect, and most flat roofs in older Broomfield buildings have at least one low spot. They hold up well to UV and stay flexible in freeze-thaw cycles.
Acrylic coatings cost less and are easier to recoat later, but they do not like standing water and need warm, dry weather to cure. We use them mainly on well-drained roofs and in the late spring through early fall window.
When a coating is the right call
The best candidate is a roof that is structurally sound and dry, with a membrane that is aging but not failing. A moisture survey comes first; if the insulation is wet the coating will simply trap that moisture and the roof will fail anyway. Seams and flashings are repaired before any coating goes on.
For a building owner with a roof in that window, a coating can push replacement out by ten years or more and is often eligible for a manufacturer warranty of its own.
When it is the wrong call
A coating cannot fix a roof with saturated insulation, structural sag, or widespread membrane splitting. It also cannot restore a roof that has been hail-fractured throughout, because the coating will bridge the cracks for a season and then follow them.
Some contractors push coatings on every roof because the margins are good. We would rather tell you a coating will not work and lose the job than coat a roof we know will leak next spring.
Hail and coatings
Coatings add a modest amount of impact protection, and thicker silicone systems do noticeably better than thin acrylic. They are not a substitute for a cover board and a heavy membrane on a roof that gets hammered every summer, but they do help an existing roof resist the small-to-medium hail that hits Broomfield most years.
After any significant hailstorm we recommend having a coated roof inspected. The coating usually shows the impact points clearly, which makes it easy to spot-repair before water gets in.