The use of liquid applied roof coatings has grown significantly over the past two decades, particularly in the repair and restoration segment. The monolithic nature (no seams) of liquid applied coatings provides ease of installation and labor savings. But perhaps the greatest driver of growth historically has been the benefit of energy savings that reflective elastomeric roof coatings provide. The origins of ‘cool roof coatings’ in the U.S. can be traced to the research and development by Rohm and Haas company in the early 1980s when comparison studies were performed on rudimentary bird houses constructed with pitched rooftops with dark asphalt shingles and white reflective coatings, and then exposed to sunny conditions. Both the outside roof temperatures and the inside temperatures showed dramatic reductions for the birdhouse constructed with a white reflective roof coating.
These initial results led to a detailed systematic study performed by Rohm and Haas in collaboration with the University of Southern Mississippi and the Mississippi Power Company in 1985. Similar buildings were constructed with flat roofs. Two flat roof buildings had identical ceiling insulation, and the same windows and doors. Both flat roofs were waterproofed with a black asphalt coating. The only marked difference was that the second building had a liquid applied reflective white roof coating added on top of the asphalt coated roof. The summer energy consumption (air conditioning) of the building containing the reflective coating was 21.9 percent lower than the ‘control’ house with the black asphalt coated roof. These results spawned numerous additional studies by various companies/agencies/municipalities confirming the energy saving benefits of reflective roof coatings.1