UN-HABITAT in partnership with the Ministry of the Environment, ENERCON and the Capital Development Authority Islamabad, under the flag of Delivering as One UN Pakistan Joint Programme for the Environment, Outcome 5: Green Building initiated a Project to demonstrate and test measures to improve the thermal performance of housing, specifically to improve Reinforced Cement Concrete (RC) flat roofing. The project has two phases: 1. Research, testing and analysis, 2. Promotion and awareness. This report documents the work carried out under phase 1, and information materials developed for promotion under phase 2. The applications have been carried out on single storey Government houses in Street 31 of Sector G-6/1 Islamabad in partnership with the Capital Development Authority. All houses of the same specification and condition were selected so as to compare the results.