SAP Assessments and Energy Performance Certificates

The Standard Assessment Procedure (SAP) is the Government approved method for producing home energy ratings, thereby demonstrating the energy efficiency of a new dwelling.

SAP assessments (also known as SAP calculations or CO₂ emission rate calculations) are generated using the SAP methodology. These calculations are a mandatory requirement and must accompany all Building Regulations submissions for new dwellings.

SAP assessments are used to show compliance with Approved Document L1 (Part L) of the Building Regulations at the design stage; they calculate the energy cost and carbon emissions generated to heat, light, ventilate and provide hot water to the dwelling. Further calculations will be required for the building as it is constructed to take account of any changes that have occurred during the build process.

At this stage Building Control will request sight of the Energy Performance Certificate (EPC), which can be generated as part of the SAP assessment. EPC’s are required for all newly built dwellings and must be entered onto a national register by an accredited energy assessor.

By law, Energy Performance Certificates (EPCs) for new dwellings can only be produced by an accredited On Construction Energy Assessor. The purpose of this is to protect the building owner by making sure that such assessors have the appropriate skills to carry out energy assessments. In order to produce an EPC, the assessor will need to use an approved version of SAP software.