The Cool Roofing Materials Database was created in 1998 and may not be current.
General Description
Roofing membranes are fabricated from strong, flexible, waterproof materials. They may be applied in multiple layers,as in the venerable Built-Up Roof (BUR), or they may consist of a single-ply membrane. Membranes usually contain a fabric made from felt, fiberglass, or polyester, for strength, which is laminated to or impregnated with a flexible polymeric material.The polymeric material may range from bituminous hydrocarbon materials such as asphalt, to synthetic rubber known as EPDM, to synthetic polymers such as polyvinyl chloride (PVC). The color of the polymer itself ranges from black to white, often depending on the amount of carbon black present. The upper surface of the membrane may be coated with a pigmented material which determines the color and solar reflectance, or it may simply be ballasted with roofing gravel. When a dark membrane is surfaced with roofing granules, the membrane has the appearance (and solar reflectance) of asphalt shingles.
For roofs ballasted with gravel, approximate values may be found at the end of this table, measured by Reagan and Acklam.
| Product | Solar Reflectance | Infrared Emittance | Temperature Rise | Solar Reflectance Index | Reference |
|---|---|---|---|---|---|
| Gray EPDM | 0.23 | 0.87 | 68 F | 21 | FSEC 1 |
| White EPDM | 0.69 | 0.87 | 25 F | 84 | FSEC 1 |
| Black EPDM | 0.06 | 0.86 | 83 F | -1 | FSEC 1 |
| Hypalon | 0.76 | 0.91 | 18 F | 95 | FSEC 1 |
| T-EPDM | 0.81 | 0.92 | 13 F | 102 | FSEC 1 |
| Firestone SBS Bitumen on White | 0.26 | 0.92 | 63 F | 28 | FSEC 1 |
| Smooth Bitumen | 0.06 | 0.86 | 83 F | -1 | FSEC 1 |
| White Granular Surface Bitumen | 0.26 | 0.92 | 63 F | 28 | FSEC 1 |
| Carlisle Syntec System Brite-Ply | 0.77 | 0.90 | 17 F | 96 | LBNL 1 |
| Ecology Roof | 0.80 | 0.90 | 14 F | 100 | LBNL 1 |
| Hypsam Roofing Systems, Hyload | 0.75 | 0.90 | 19 F | 93 | LBNL 1 |
| *Sarnafil Beige | 0.43 | 0.92 | 49 F | 49 | LBNL 4 |
| *Sarnafil Blue | 0.61 | 0.92 | 32 F | 73 | LBNL 4 |
| *Sarnafil White | 0.83 | 0.92 | 11 F | 104 | LBNL 4 |
| Stevens Hi-Tuff EP white | 0.78 | 0.9 | 16 F | 97 | LBNL 1 |
| Trocal Roofing Systems, White | 0.77 | 0.9 | 17 F | 96 | LBNL 1 |
| Trocal Roofing Systems, White | 0.83 | 0.9 | 11 F | 104 | LBNL 1 |
| Dark gravel on BUR roof | 0.12 | 0.9 | 76 F | 9 | Reagan |
| Light gravel on BUR roof | 0.34 | 0.9 | 57 F | 37 | Reagan |
| White-coated gravel on BUR | 0.65 | 0.9 | 28 F | 79 | Reagan |
*represents new data