We often receive enquiries about the differences between an Energy Performance Certificate (EPC) for new buildings and one for existing structures. This article clarifies these distinctions and explains the methodologies involved.
What is a SAP EPC?
A SAP EPC is an Energy Performance Certificate issued by an ‘On Construction Domestic Energy Assessor’ using the Standard Assessment Procedure (SAP) methodology. This is otherwise knows as a SAP Assessment.
The certificate is essential for any new dwelling or properties created through conversion or change of use in the UK.
How is a SAP EPC Created?
The process for obtaining a SAP EPC involves the following steps:
- Assessment Preparation: The assessor uses architectural plans and detailed information regarding construction, heating, and ventilation systems.
- SAP Calculations: Using SAP software, the assessor measures the energy performance of the newly constructed home.
- EPC Generation: Finally, the assessor produces the EPC, which outlines the energy efficiency rating of the build.
EPCs for Existing Dwellings
Most EPCs are required for existing dwellings, typically when properties are sold or rented. Previously, these EPCs were part of the Home Information Pack (HIP) for prospective buyers or tenants, but HIPs have since been phased out.
How is an EPC for Existing Dwellings Created?
New homes must be certified by a SAP Assessor
The process for existing buildings is different:
- On-Site Assessment: A Domestic Energy Assessor (DEA) visits the property to conduct an in-person survey.
- RDSAP Methodology: The assessor employs a simplified energy assessment method known as RDSAP (Reduced Data SAP). If it’s challenging to determine the construction specifics through inspection, RDSAP uses age-related values and assumptions to assist the assessment.
Key Differences Between a SAP EPC and an Existing Dwelling EPC
While both EPC types serve the same purpose—providing insights into energy efficiency and associated costs—they differ significantly in their methodology:
- SAP EPC: Based on detailed construction specifications and architectural drawings.
- EPC for Existing Dwellings: Derived from a physical site survey using the RDSAP methodology.
Generally, an EPC for an existing dwelling is less expensive to obtain than one based on SAP calculations.
Contact Us for SAP Assessments
Would you like to discuss your project or learn more about obtaining an EPC for a new home?
Call us at 0330 055 34 05 or email be@buildenergy.co.uk for a consultation.