SAP calculations have long been required of housebuilders, but as of April 6 2008, energy performance certificates (EPCs) have become mandatory for all new homes completed since that date in England and Wales. It will become mandatory for new homes in Northern Ireland from September 30, whilst the requirements of the energy performance of buildings directive were implemented in Scotland in 2007. The EPC tells prospective buyers about the energy efficiency and environmental performance of a home. <br><br>It is an additional document, an extension of the energy rating process that starts at design stage with the SAP. Once a SAP is calculated, a predicted energy assessment can be provided. This is mandatory for all homes that are sold off-plan and require a HIP, as the EPC can only be provided on completion when a property actually has been built. Your energy assessor must be trained and OCDEA accredited, and for new build will not need to visit the property. In order to complete the EPC, the assessor needs to know whether there have been any design changes on construction, as well as the air leakage test results for plots which have been tested. It is the assessor’s responsibility to register …