Conventional roofs are typically dark and retain sunlight as heat. When the temperature rises, these dark roofs absorb heat, which increases roof and building temperatures, building cooling costs, and local temperatures in urban settings because of the urban heat island effect. These effects can be reduced by painting roofs with a white coating, which reflects the sun’s heat instead of absorbing it.
In its first year, the Cool Roofs initiative will:
Coat the roofs of 10 City-owned buildings, approximately 50,000 square feet.
Reduce average electricity used in these building by 10-15% per month.
Reduce CO2e emissions in Pittsburgh by 45 metric tons and reduce the urban heat island effect.
Engage 200 volunteers.
Cool Roofs reduces cooling costs.
Cool Roofs lowers roof temperatures, which lowers building temperatures. Subsequently, the amount of energy needed to cool the building with air conditioning, fans, etc. is also reduced.
Cool Roofs increases roof longevity.
Temperature fluctuations cause roofs to expand and contract. This temperature fluctuation can damage roofs over time. White coated roofs experience less temperature fluctuation and less damage over time.
Cool Roofs reduces the urban heat island effect.
Have you ever noticed that urban environments seem hotter in the summer than their rural counterparts? This is because of the urban heat island effect. High concentration of dark material causes urban environments to experience a temperature increase of up to five degrees. Cool Roofs combats the urban heat island effect by reducing the concentration of dark, sunlight-absorbing surfaces.
Cool Roofs reduces greenhouse gas emissions and pollution by lowering the demand for energy use.
Buildings with white coated roofs do not need to use their cooling or HVAC equipment as often as dark roofs, which improves equipment longevity.