SAP Report and Calculations

SAP reports are produced using the Standard Assessment Procedure to provide evidence of compliance to Building regulations Part L;  for all new build properties, conversions and extensions where the glazed area is over 25% of the floor area.

The regulations were amended in 2006 with the introduction of Approved Document L1A for New Build and L1B for Existing Homes including Extensions. The SAP report is the UK government’s approved method of assessing a building’s energy performance and is now mandatory for all new build dwellings. It is also complusory for all new dwellings to provide the prospective property owner with a full Energy Performance Certificate (EPC).

The SAP calculation is undertaken at the design stage of the build and the SAP assessment is carried out taking into account a range of factors which contribute and effect the energy efficieny of the property.

The SAP report makes calculations based upon:

  • Building materials used to construct the property
  • The building materials thermal insulation properties
  • Characteristics of the ventilation system of the property
  • Efficiency and control of the heating system
  • Type of fuel (for eg gas, LPG, oil) which will be used to supply water and space heating
  • Renewable energy sources utilised for e.g. solar or wind
  • Solar gains via openings of the property