Properties and performance of an innovative reflective painting to reduce the coolingloads in buildings and mitigate the heat island effect in urban areas

High reflective coatings and paintings for the building envelope can be very useful to reduce the cooling loads and ensure thermal comfort conditions in the built environment.A sustainable painting obtained with a specialmixture of milk and vinegar is able to reach very high solar reflectance for light colours and especially for the bright white was tested during summer 2006 and used for roofs and walls for several purposes. The solar reflectance of this materials and of usual construction materials was measured with a spectrophotometer. A surface temperature monitoring campaign run for severalweeks in order to compare the thermal profiles of the white painting with those o materials generally used in Italian buildings.The last part of the campaign included the monitoring in two identical rooms of the experimental building Casa Intelligente of ENEA, with indoor and outdoor air temperatureand roof surface temperatures monitoring. This monitoring campaign allowed to verify the influence of cool roofs to mitigate the indoor air temperatures and reduce the heat island. Dynamic simulations were performedthe influence of cool roof in office buildings to reduce the cooling demand and peak.