The Flat-to-Slop Roof Renovation Program evaluation of the first pilot project in Shanghai has been completed recently. After renovation, the inside temperature is 3-5 degrees lower than before in summer. As a result, the electricity costs saving is about 10%-15%.

According to the statistics, the annual average energy consumption will be decreased 10% after renovation. And it will gain 4.8 yuan as profit per square meter per year. The budget of renovation is around 70 yuan per square meter approximately, the cost will be covered in 15 years.

The government of Shanghai is planning a further renovation projects, includes 40 residential areas which is about 4 million square meters in total. The renovation includes replacement of windows and doors, but also external insulating.