These reflective coatings are usually water-based acrylic elastomers, and can be applied to your roof with a simple roller. The coatings can be installed on most low-slope roofing materials including metal, asphalt, or single-ply membranes. Some underlying materials should have a primer applied before applying the reflective coating in order to ensure that the material can get the proper adhesion.
If you’re considering installing a cool roof coating on your home’s roofing system, the first thing to do is to educate yourself about the types of coatings available. Look specifically for a coating that has an Energy Star rating. Next you’ll need to prepare your roof for the application. This is one of the most important parts of the process. The underlying roofing materials need to be clean so the coating can be secured and stay for years. Roof coating will never stick to roofs that are dirty or greasy. You also shouldn’t use the coating in effort to repair a damaged roof.
To install a cool-roof coating properly you should follow this procedure.
- Clean the roof. Make sure it is clear of debris, leaves and loose shingles.
- Wash the roof with water/ trisodium phosphate solution.
- Reinforce open joints around pipe flashing roof drains or HVAC equipment.
- Repair cracks and blisters.
- For metal roofing, sand and repair rusted areas.
- Prime uncoated galvanized iron.
- Gather tools for the application. You’ll need a 1-1.5 inch roller on a 6 foot pole. A large brush for edges. Work clothes and shoes and finally disposable rags.
- Read the instructions on the side of the can of cool-roof coating as it pertains to coverage.
- Use drop cloths and tape to cover anything you don’t want to get the coating on like windows, siding, cars or plants.
- Only apply the coating when there is no risk of rain or other forms of precipitation. Wetness will weaken the bond between the coating and underlying roofing.
- Use a brush to coat the edges, corners and jacks around pipes. Use the roller for larger open areas. Always install two coats leaving time for a day between coats for curing. Apply the second coat in the opposite direction than the first for optimal coverage.