Cool Roof & Radiant Barrier Strategies — FarmPal
Roof surfaces receive the most intense solar radiation addressing the roof is the single highest-impact cooling intervention. White or light-colored roofing (solar reflectance index >78) reduces roof surface temperature by 50-60°F compared to dark roofing. Living/green roofs provide R-5 to R-10 insulation plus evapotranspiration cooling surface temps stay within 10°F of ambient even in full sun. Radiant barriers (reflective foil under the roof deck) block 95% of radiant heat gain from reaching the attic most effective in hot climates with south/west exposure. Double roof (ventilated air gap between outer and inner roof): the air gap acts as a thermal buffer, reducing ceiling heat gain by 30-50%. Combine strategies: ventilated double roof with radiant barrier + light exterior color achieves near-zero radiant gain.
Roof surfaces receive the most intense solar radiation addressing the roof is the single highest-impact cooling intervention. White or light-colored roofing (solar reflectance index >78) reduces roof surface temperature by 50-60°F compared to dark roofing. Living/green roofs provide R-5 to R-10 insulation plus evapotranspiration cooling surface temps stay within 10°F of ambient even in full sun. Radiant barriers (reflective foil under the roof deck) block 95% of radiant heat gain from reaching the attic most effective in hot climates with south/west exposure. Double roof (ventilated air gap between outer and inner roof): the air gap acts as a thermal buffer, reducing ceiling heat gain by 30-50%. Combine strategies: ventilated double roof with radiant barrier + light exterior color achieves near-zero radiant gain.