A series of tests were conducted in seven retail shops in Cocoa, Florida to examine how roof whitening would impact air conditioning load. The roof of the strip mall was conventional: un-surfaced galvanized corrugated metal with R-11 insulation suspended by purlins underneath. The roof was resurfaced white at mid-summer using commercially available roof coating product. The measured roof reflectivity was altered from approximately 29% to 75%. The tests were phased over a two summer period so that impact of surface degradation could be measured in the second year of exposure.
The results for both phases of the project, showing a 25.3% average reduction (8.6 kWh) in summer space cooling per day with ranges between 13% and 48%.
Parker, D., Sonne, J., Sherwin, J. Demonstration of Cooling Savings of Light Colored Roof Surfacing in Florida Commercial Buildings: Retail Strip Mall. Florida Solar Energy Center/University of Central Florida. Final Report October 1997. FSEC-CR-964-97.
Source: Florida Solar Energy Center/University of Central Florida
Publication Date: October 1997