- SAP
- Standard Assessment Procedure: the government methodology that calculates the energy score behind an EPC band. Full SAP is used for new builds. More →
- RdSAP
- Reduced data SAP: the survey-based version of SAP used for existing homes. Version 10, live since June 2025, made inputs evidence-based. More →
- HEM
- Home Energy Model: the half-hourly calculation engine due to replace SAP and RdSAP, with PRS assessment switching to HEM-derived metrics from October 2029. More →
- MEES
- Minimum Energy Efficiency Standards: the rules setting the lowest band a rental may have. Currently E; band C equivalent from 1 October 2030 for private lets in England and Wales. More →
- EER
- Energy Efficiency Rating: the headline A to G chart on the current certificate, based on modelled running costs. More →
- EIR
- Environmental Impact Rating: the second A to G chart on older certificates, scoring CO2 emissions rather than cost. Never acquired legal force for domestic lets. More →
- Lodgement
- The act of filing a completed EPC on the official register, which is when its 10-year validity starts. Assessors pay their scheme a fee per lodgement. More →
- DEC
- Display Energy Certificate: the annual operational-energy certificate large public buildings must display. Not an EPC, though frequently confused with one. More →
- PRS Exemptions Register
- The public register where landlords record MEES exemptions with evidence. An unregistered exemption is not an exemption. More →
- SBEM
- Simplified Building Energy Model: the calculation behind non-domestic EPCs. More →
- Cost cap
- The most a landlord must spend attempting compliance: £3,500 inc VAT under the current E floor, £10,000 under the confirmed 2030 band C standard. More →
- Potential rating
- The band your certificate says the property could reach if all its recommendations were carried out. More →
Missing something? The FAQ answers the question-shaped versions, and the meanings index covers the acronym's five other lives.