White Roof Paint is White Elastomeric Roof Coating
White roof paint is different than normal exterior paint. It’s elastomeric, which means that after drying, it resembles rubber, yet resumes its original shape when a deforming force is removed, and it’s reflective. Reflecting the sun’s light and UV rays means it’s also reflecting the sun’s heat – and that is where the cost savings comes into play. The less heat the sun adds to a building, the less electricity it will cost to keep that building cool. And not only does white, reflective, elastomeric roof paint coatings reduce air-conditioning cost and lower roof and interior temperatures, it also seals roofs to prevent leaks.
Most white roof coating paint is acrylic elastomeric resin like liquid rubber, which resists cracking and peeling, and expands and contracts up to 350%. It can be applied with a brush, roller, or via spray application. Different brands of paint have different peel strengths, solids count, solar reflectance values (also known as albedo), and thermal emittance. Premium white coatings reflect 90% or more of the sun’s rays by forming a thick rubber-like blanket of protection and reflection. Albedo solar reflectance is expressed either as a decimal fraction or a percentage. A value of 0 indicates that the surface absorbs all solar radiation, and a value of 1 represents total reflectivity. Thermal emittance is also expressed either as a decimal fraction between 0 and 1, or a percentage.
Another method of evaluating coolness is the solar reflectance index (SRI), which incorporates both solar reflectance and emittance in a single value. SRI quantifies how hot a surface would get relative to standard black and standard white surfaces. It is defined such that a standard black (reflectance 0.05, emittance 0.90) is 0 and a standard white (reflectance 0.80, emittance 0.90) is 100. The use of SRI as a combined measurement of reflectance has been disputed, since it has been shown that two different products with identical SRI numbers can yield significantly different energy savings results depending on what geographic region they are applied in, and the climatic conditions present in this region.
3 of the Most Popular White Roof Paint Elastomeric and Relective Coatings
|Kool Seal® Premium White Elastomeric Roof Coating (63-600) is formulated with 100% acrylic elastomeric resin. The coating forms a thick rubber-like blanket of protection that expands and contracts with roofs. It remains flexible from -30°F to 160°F for long-lasting protection and provides superior reflectivity to lower interior temperatures and save energy. Kool Seal® Premium White Elastomeric Roof Coat adheres to aged galvanized and prepainted metal, urethane and polystyrene, aged aluminum coating, precast concrete, flat and barrel cement tiles. For use on built-up roofs, modified bitumen, bonded tar & gravel, most other asphaltic surfaces and in ponding water situations, Kool Seal® Kool-Lastik™ Primer (34-600) is required.
|Henry’s HE287 – SOLARFLEX® Elastomeric Roof Coating is a premium, elastomeric, water-based acrylic latex coating. Properly applied, it is highly resistant to disbonding, chalking, mildew and discoloration. It can be used on well-drained surfaces which do not “pond” water; conventional, SBS, or APP mineral surface cap sheet; smooth surface built-up roofing, SBS, APP, or metal which has first been coated with conventional Henry #107® Asphalt; emulsion; stucco parapet walls; and roof surfaces previously coated with white or aluminum (aluminum must be allowed to weather a minimum of 90 days before coating. For warranty information, visit Henry.
|Liquid Rubber® which is the ONLY liquid form of EPDM in the world, is a unique form of EPDM rubber. As a liquid, it can conform to any shape of surface, ?ashing or protrusion, vertical or horizontal, and can be applied easily with a paint brush or roller. When mixed with a catalyst it cures by chemical reaction to form a self adhering solid seamless rubber sheet. Liquid Rubber® is a versatile coating for a broad range of applications. Its superior protective quality is derived from a unique combination of physical and chemical properties. Its EPDM chemistry provides for long durability, water resistance, a broad temperature tolerance and chemical resistance. As a chemically curing Liquid Rubber® it can form a ?exible membrane up to 25 mils thick in one coat. The exposure environment can vary from high humidity to total immersion; constant or cyclic temperature changes from minus -60 F to 300 F or corrosive environments consisting of vapors, liquids and salt solutions.