SAP is the Standard Assessment Procedure for the Energy Rating of Dwellings. SAP 2009 calculates the energy performance in buildings and is used to provide energy ratings in dwellings. It also demonstrates compliance with Building Regulations.
The SAP rating is based on the energy costs associated with space heating, water heating, ventilation and lighting minus the cost savings from energy generation technologies. SAP ratings are expressed on a scale of 1 to 100, the higher the number meaning the lower the running costs.
The method for calculating the energy performance and ratings is set out in the form of a worksheet. The calculation should be carried out using a computer programme that implements the worksheet and is approved for SAP claculations.
You can find the SAP efficiency of a HETAS Approved Appliance using the Find Appliance search facility.
For further information on SAP visit the Department of Energy and Climate Change (DECC) website.