摘要 |
A four component roofing system uses three reflective subsystems and one radiant subsystem to provide passive temperature control of a building comprising: (1) Shingles that reflect high angle summer sun light back to the sky, but absorb low angle winter sunlight; (2) A temperature sensitive attic insulator placed under a sunlit roof that reflects radiation and blocks convection from the roof to the attic at hot temperatures, permits radiation and convection at warm temperatures, and blocks radiation and convection from the attic at cold temperatures; (3) A temperature sensitive attic insulator placed under a shaded roof that permits radiation and convection at warm or hot temperatures, and blocks radiation and convection from the attic at cold temperatures; (4) Non-reflective shingles on a shaded roof that emit radiation continuously, but that are heated by air and radiation from the attic only when the second temperature sensitive attic insulator permits convection, so that radiant heat loss is reduced at cold temperatures. |