Requires that all new homes and buildings for sale must undergo an energy performance evaluation (an energy performance diagnostic, or DPE), and receive an energy performance certificate. The certificate indicates both the level of energy consumption and the greenhouse gas (GHG) emission level, on a scale of A to G, with G being least efficient and highest GHG emissions. The diagnostic must be accompanied with recommendations on improving the buildings energy efficiency. The diagnostic and certificates must also be provided for rentals, and is to be provided for all new construction where the building permit was submitted after 1 July 2007. DPE applies to all public buildings, and public display of the certificate is mandatory.