Insulation Plays Key Role in Building Efficiency
Specifiers often refer to cool, or highly reflective, roofing as green. But does a roof have to be cool to be green? Manufacturers of cool roofs promise energy savings from their products, but in many cases, managers can achieve similar results with the proper use of roofing insulation.
Insulation can play a crucial role in the energy efficiency of buildings. But in facilities that lack insulation and are located in warmer parts of the country, white reflective coatings and reflective aluminum coatings might offer some energy-saving benefits, and they can reduce air-conditioning costs.
These reflective coatings can save energy, but they do not solve all energy problems, and managers should not omit insulation from building construction when specifying reflective coatings.
Reflective coatings can reduce roof temperatures. Roofing material manufacturers have invested in technology and equipment to produce granulated white or reflective cap sheets for modified bitumen membranes. Capping an asphalt BUR or modified bitumen system with a white surface and performing proper maintenance can deliver energy savings and extend the systems’ life cycle.
Managers also can coat a BUR system with a bituminous coating or imbed light-colored gravel into a flood coat of asphalt. These solutions result in more reflective surfaces.
Research continues as to when the use of reflective roof surfacing makes the most sense. In cooler climates, no real justification exists for white or reflective surfaces related to energy savings because buildings in these areas tend to require insulation for protection against low temperatures in the winter, which also reduces cooling loads in warmer months.
Nonetheless, solid arguments exist for the use of high-quality roof coatings to extend the performance lives of asphalt BUR and modified bitumen roofing systems.