Conclusions
Fiberglass roofing shingles, tiles, and metallic materials comprise over 80% (by roof area) of the
U.S. western region residential roofing market. In cooling-dominated regions, increasing the
solar reflectance of the roof lowers air-conditioning use in a cooled building and improves
comfort in an unconditioned building.
Our analysis has suggested that cool-colored roofing materials can be manufactured using the
existing equipment in production and manufacturing plants. The three principle ways to improve
the solar reflectance of roofing materials including: (1) using of raw materials with high solar
reflectance, (2) using cool pigments in the coating; and (3) applying a two-layered coloring
technique using pigmented materials with high solar reflectance as an underlayer. Although all
these options are in principle easy to implement, they may require changes to current production
techniques that may add to cost and market competitiveness of the finished products.
Application of cool-colored pigments in metal roofing materials may require the least change to
the existing production processes. As in the cases of tile and fiberglass shingle, cool pigments
can be applied to metal via a single or a double-layered technique. If the raw metal is highly
reflective, a single-layered technique may suffice.
Additional quality control measurements may be required to verify that coatings are truly NIRreflective.