- Roof coating
A roof coating is a monolithic, fully adhered, fluid applied
roofing membrane. It has elastic properties that allows it to stretch and return to their original shape without damage.
Typical roof coating dry film thickness vary from
paintfilm thickness (plus or minus 3 dry mils) to more than 40 dry mils. This means a roof coating actually becomes the top layer of a composite roof membraneand underlying system. As such, the roof coating is the topmost layer of protection for the membrane, receiving the impact of sunlight (both infrared and ultraviolet (UV), rain, hail and physical damage.
A roof coating can be applied by brush, roller or spray. An airless sprayer is recommended for best results.
Field-applied reflective roof coatings can extend the useful life of nearly every
roofsubstrate by keeping a roof surface cool and providing a level of protection from the sun and weather. Field studies have shown that a reflective roof coatings can lower rooftop temperatures and reduce air conditioning bills. [http://www.lexiscoatings.com/articles.php/reflective-roof-coatings]
An adhesion test must be done to ensure compatibility with the existing substrate.
*PreparationInspect the roof for flaws, loose fasteners, cracks, gaps or tears. These need to be fixed before the roof is pressure washed. The roof surface must be thoroughly cleaned by pressure washing using a biodegradeable detergent. Allow the roof to dry thoroughly before applying any coating.
*PrimerPrimers improve the adhesion between the existing roof substrate and topcoat. On some roofs, priming may be optional but they are a small price to pay for peace of mind. If in doubt, always use a primer.
*Coating ApplicationThe roof coating is usually applied in 2 to 3 separate layers. Always let the last coat dry before putting another one on. The base coat may be tinted to facilitate drying and to ensure even coverage of the finish coat.
* [http://www.epa.gov/hiri/strategies/coolroofs.html EPA.gov: Cool Roofs]
* [http://www.energystar.gov ENERGYSTAR.gov: Energy Star]
title = Reflective Roof Coatings Improve A/C Efficiency
publisher = Lexis Coatings
last = Cua
first = Alexander
* [http://coolroofs.org/codes_and_programs.html Cool Roofs]
* [http://coolcolors.lbl.gov Cool Colors Project]
* [http://eetd.lbl.gov/HeatIsland/CoolRoofs/HeatTransfer/#Sunlight Heat Island]
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