White painted roofs reduce energy use (but by how much?)

New research launched by the University of Melbourne and the City of Melbourne will give buildings owners across Melbourne access to information that can help their buildings absorb less heat and stay cooler during hot days.

http://newsroom.melbourne.edu/news/n-739

Unfortunately this news report lacks detail on the results of the research, other than using the word "significant" in relation to temperature reductions within buildings achieved by painting the roofs white.   However there is further information on the website

http://www.melbourne.vic.gov.au/1200buildings/Pages/Home.aspx

which is part of Melbourne's goal of becoming carbon neutral by 2020.