This process was developed to refinish old concrete rooftile, clay tile and fiber cement tile. It has proven to be effective at enhancing the appearance of a roof and to be durable against a variety of environmental conditions. As you can see, the rooftile to the right (from a roof in Southern California), shows moss and algae which has built up over 10 years.  

In addition to enhancing appearance, a refinished roof can save energy by using Cooltile IR Coatings™ and gloss topcoat, and is a much lower cost alternative to replacing a roof.  The refinishing process consists of the following five steps:

The first step is for the homeowner and roof restoration specialist to evaluate the condition of the roof and to agree to specific remedies to fix fundamental problems, such as leaks or broken tiles. Then the roofing specialist must prepare the house for powerwashing the roof by protecting adjacent surfaces from runoff, staining or overspray. Polyfilm, masking tape, cardboard and gutter-guards maybe required in protecting adjacent areas.

The second step is two powerwashing cycles at 4000 PSI with a biocide treatment in between. This is done to remove dirt, algae, efflorescence, corrupted slurry coat and other surface contaminants. 

After the first powerwashing, the rooftile is treated with bleach in those areas effected by mold, algae, lichen, moss, and other plant life. After allowing the bleach and sunlight to kill-off microbes, a second powerwashing is completed to remove any remaining contamination including residual bleach.  

The third step is to apply two penetrating binder coats that strengthen the upper surface of the tile and allow good adhesion of the subsequent color coats. The first application at 0.2 gallon per square is usually absorbed quickly and should be allowed to dry at least an hour before applying the second coat at 0.13 gallon per square. These two coats are best allowed to dry overnight before continuing with application of the color coat. This polymer binder prevents subsequent coatings from peeling, blistering or removal by scuffing.

The fourth step is application of a 100% pure acrylic color coat that contains a biocide to prevent unsightly organic growth. The color coat is applied in two coats to insure uniform color appearance and uniform film build. The first coat is best applied at 0.3 gallon per square and the second coat is best applied at 0.2 gallon per square. With sixteen colors available there is likely one that suits a homeowner’s taste. The application of two or more colors can be done to achieve a ‘flashed’ or multi-colored blend appearance. Special order colors and custom colors can be matched with a minimum order.

The fifth and final step is the application of a single clear gloss topcoat. The topcoat is a hard 100% acrylic polymer coating, including a biocide to control unsightly organic growth, that increases the life of the finish nearly twofold and it gives a uniform gloss to the entire roof surface. A low sheen clear topcoat can be used which gives a softer lower gloss appearance. In either case the topcoat is applied at 0.25-0.33 gallon per square in one pass.