Cool Roofs and Pavements are designed to reflect more sunlight and absorb less heat than a standard roof and pavement. Cool Roofs and Pavements are identified as components that are able to deliver high solar reflectance and high thermal emittance. They reduce heat load for air conditioning system, energy usage and CO2 released to the atmosphere. Cool Roofs can be made of a highly reflective type of paint, a sheet covering, highly reflective tiles or shingles. Standard roofs can reach temperatures of 65°C or more in the summer. A cool roof under the same conditions could stay more than 10°C cooler. The same applies for Cool Pavements
In the ReCO2ST project, cool materials will be exploited for residential applications and microclimatic interventions. Research shows that CO2 emissions can be reduced by 1.9 to 7.5 kg/m2 of cool roof area. Furthermore, the urban heat island effect can be mitigated through cool materials by reducing air temperatures at city scale by 1-2°C on average, as less heat transfer from a cooler surface to the ambient air. Moreover permanently retrofitting urban roofs and pavements in the tropical and temperate regions of the world with solar-reflective materials would have an equivalent effect on global temperatures as inhibiting the emissions of 44 billion tonnes of CO2, or over one year’s worth of humanity’s CO2 emissions.