New EPC rules: the Home Energy Model and four metrics, explained

Last updated 27 July 2026·Applies to England & Wales

The government is reforming how Energy Performance Certificates are produced and what they measure. The planned move is from today's RdSAP methodology to certificates based on the Home Energy Model, with four headline metrics instead of one cost-based score. This guide explains what's changing, the intended timeline, and what owners and landlords can sensibly do while the detail is finalised.

How today's EPC works

A current EPC scores a property from 1–100 using RdSAP, and the score is driven largely by estimated energy cost. Band D covers 55–68 points and band C starts at 69. That cost basis has a known quirk: measures that cut bills (like solar panels) can flatter the score without improving how well the building itself retains heat.

What the reformed EPC would measure

The government's plans describe certificates based on the Home Energy Model with four headline metrics:

Fabric performance — how well the walls, roof, windows, floors and airtightness retain heat. This is the headline, "fabric-first" measure.
Heating system — the efficiency and type of the heating.
Smart readiness — how well the home can use smart tariffs, storage and flexible energy.
Energy cost — the running-cost view, closest to today's score.

The intended timeline

Planned launch in the second half of 2027 for Home Energy Model certificates.
Parallel running until at least October 2029 — current-style and reformed EPCs are intended to run side by side during the transition.
1 October 2030 — the government's announced MEES policy would require rented homes to reach the equivalent of C on fabric performance, plus C on either smart readiness or heating system. See our EPC C by 2030 guide.

Status: these are announced government plans, not law. Launch dates have moved before and the final metric definitions, and the MEES policy that would use them, remain subject to consultation outcomes and Parliamentary approval. Check the certificate and legislation in force before making decisions that depend on the reform.

What to do now

Check the EPC you have — rating, score, expiry and the recommendations list. Our EPC checker shows it in context.
Favour fabric measures. Insulation and airtightness improve today's score and the fabric-performance metric the reformed system is built around. Bolt-on technology that only flatters the cost score is the riskier spend.
Landlords: consider locking in a C early. Under the announced policy, a current-style C achieved before 1 October 2029 would be grandfathered — treated as compliant until the certificate expires. Costs are covered in our D-to-C upgrade guide.
Keep invoices. Qualifying spend from 1 October 2025 is intended to count towards the announced £10,000 MEES cost cap.