Restoration begins with candidacy—not a sales promise.

It should not be. Coating over an active leak traps water in the assembly, where it moves sideways through wet insulation and comes out somewhere new. The leak path has to be found and corrected first, and any saturated material taken out, before a coating is worth applying. A proposal that skips that step is offering you a finish, not a repair.

Longer if it was prepared properly and thinner than specified if it was not, which is why the written warranty is worth more than the brochure figure. The variables that actually decide it are how clean and sound the surface was, how many coats went on and at what thickness, whether the drainage works, and how much foot traffic the roof carries. Ask what thickness is being installed and how it will be verified.

From the coverage rate and the quantity of material actually used, checked against the area it covered. Coatings are warranted on dry film thickness, delivered as gallons per square, and the difference between a coating that reaches its expected life and one that does not is frequently material that never left the drum. Ask for coverage rates, batch numbers and which areas each batch went onto. Once the surface is dry, none of it can be seen.

It is recoated, it is replaced, or the first choice constrains both. The chemistry that went on first limits what the second one can be — most sharply with silicone, which very little else will adhere to — so the exit is effectively decided at the first application rather than a decade later. Ask what that exit looks like before anything is applied, and make sure the record says which product went on.