Information
Roof coatings vs replacement.
A fluid-applied coating can add years to a sound low-slope roof. It cannot resurrect a membrane that has already let go. Same honesty as the foam page: decide the deck first.
Information
Maintenance on a sound roof. Not a miracle on a failed one.
1. When a coating is maintenance
The existing membrane is still adhered, seams are mostly intact, the deck is dry, and drains still move water. A compatible coating at the specified dry-film thickness can renew UV protection and buy a defined number of years. That is maintenance. It has a recoat date.
2. When it is paint over a dead membrane
Open seams, wet insulation, rusted deck, blisters you can step through, or a covering that has already split at the flashings. Coating that assembly seals the water in and makes the next tear-off heavier and more expensive. If the bid does not include core cuts or moisture readings, it is guessing.
3. Ponding and adhesion tests
Standing water after 48 hours is a slope and drain problem. Most coatings are not designed to live underwater. Fix drains and low spots first, or the coating fails in the puddle.
Adhesion tests — pull tests on the actual roof — tell you whether this product will stick to this dirty, chalky, previously coated surface. A data sheet from another job is not a test.
4. Warranty traps
- Material-only warranties that ignore labor and ponding
- Warranties voided if the recoat interval is missed
- Warranties that exclude existing wet insulation the crew never opened
- “Lifetime” language on a product with a five-year film
5. Removal cost later
Layers of coating plus a failed membrane are a heavier tear-off. Budget that now if the honest path is replacement in five years. A cheap coating can be the most expensive way to postpone a reroof.
6. Questions to ask
- Did anyone core the roof or run a moisture meter?
- What is the adhesion test result on this surface?
- Where does water stand after a rain, and what changes that?
- What dry-film thickness, and when is the first recoat?
- If this fails, what does tear-off cost with the coating on it?
CGC1540882 · CBC059473 · CCC1330892 · CPC1458687
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