A combined experimental and analytical  study was conducted to  quantify the energy savings for cool roof membranes.  SPRI and several members of SPRI enacted user agreements with ORNL to study the effect of climatic exposure on the surface properties of single ply membranes. SPRI and its affiliates field-tested for three years their single ply low slope roofing systems on the western  half of the Envelope Systems Research Apparatus (ESRA).  The single  ply membranes tested in the study were thermoplastics, bitumen-based membranes,  and thermoset membranes covered with 15 lb/ft 2 or 73 kg/m2 of ballast. The thermoplastics membranes tested were polyvinyl chloride (PVC), polypropylene or thermoplastic polyolefins (TPO).

Experimental work included the initial measurement of reflectance and a subsequent measurement every fourth month. Emittance was measured annually. Field data of the temperature and heat flux were organized and plotted weekly for comparing the cool membranes against the BUR. Candidate single ply membranes were also exposed at field sites across the country, and reflectance there was measured semiannually to observe the effect of climate.