According to the Building Design and Construction, it has now been proved that the white roof is very efficient when it comes to have a cooling effect on the building. So next time when you think about reducing the air conditioning bill of your building, make sure you install white roof and change the pavements to more reflective materials such as concrete instead of asphalt based material. Globally roofs account for 25% of the surface and the pavement accounts for 35% of the space in a city so going ahead with the more reflective material will clearly help the individual buildings as well as the environment.
As a proof of concept a project was under taken by The City of Tuscan USA and upto 50% improvement was noticed in the energy requirement to cool the building after the roofing was converted to white roof.