EPC Rating Bands
Understanding the A–G Scale
EPC ratings are calculated using the SAP (Standard Assessment Procedure) score, which runs from 1 to 100. The higher the score, the more energy efficient the property. The average UK home sits at around band D (SAP 55–68).
Landlord MEES Compliance
Since April 2020, all new and renewed tenancies in England and Wales must have a minimum EPC rating of E. Properties rated F or G cannot legally be let. Proposed government targets would raise the minimum to C by 2028 for new tenancies.
The Assessment
What is RdSAP?
RdSAP — Reduced data Standard Assessment Procedure — is the government-approved methodology used by accredited DEAs to assess existing homes. It calculates your property's energy use and running costs based on its physical characteristics, heating systems, and built fabric. All EPCs for existing domestic properties in the UK are produced using RdSAP.
On-site visit
The assessor physically visits the property and takes measurements and notes.
RdSAP software
Data is entered into accredited software (e.g. Elmhurst Ecoplus) which calculates the SAP score.
National register
The certificate is lodged on the official government EPC register and is publicly searchable.
Improve Your Rating
Common EPC Improvements
These are the most common recommendations that appear on EPC reports. They're ranked by cost-effectiveness.
Add 270mm+ loft insulation
+5–10 SAP points
Cavity wall insulation
+5–10 SAP points
Upgrade to A-rated combi boiler
+5–8 SAP points
Install double glazing throughout
+3–6 SAP points
Switch to 100% LED lighting
+1–3 SAP points
Add programmer & room thermostat
+2–4 SAP points
Install solar PV (3kWp system)
+8–15 SAP points
Draught-proof windows & doors
+1–2 SAP points
£ = low cost | ££ = moderate | £££ = significant | ££££ = major investment
Prepare for Your Assessment
What to Have Ready
Access to all rooms
Ensure all rooms, cupboards, and built-in storage are accessible. The assessor needs to measure every heated room.
Loft hatch access
If you have a loft, the hatch should be accessible. The assessor will need to look inside to check insulation depth.
Boiler & heating controls
Make sure the boiler is accessible and visible. If you have the boiler manual or installation certificate, have it ready — it helps identify the model for PCDB lookup.
Insulation certificates
If cavity wall or loft insulation has been installed by a professional, any CIGA or installer certificates will allow confirmed rather than assumed values.
Solar panel documentation
For solar PV or thermal, have the MCS installation certificate and system specification to hand — this gives a more accurate SAP contribution.
Meter access
Gas and electricity meters should be accessible to confirm fuel type and meter type, which affects the SAP calculation.