Domestic EPC Calculator (UK)

How This Estimate Works

An official Energy Performance Certificate is produced by an accredited assessor using the government's Standard Assessment Procedure, or its reduced version for existing homes. This calculator uses a simplified points system based on the same main factors: insulation, glazing, heating system and controls, hot water, and lighting. It gives a rough idea of your likely band and which improvements would move it most, but it can't replace a real assessment.

Improvements that usually make the biggest difference

• Loft insulation to around 270mm, often one of the cheapest upgrades.
• Cavity wall insulation where the walls have a cavity.
• A modern condensing boiler or heat pump with proper controls such as a programmer, room thermostat and thermostatic radiator valves.
• Double or triple glazing in place of single glazing.
• Solar panels, which can lift the rating as well as cutting bills.

Why the rating matters

You need a valid EPC to sell or let a home. Landlords in England and Wales must currently meet at least band E unless an exemption applies. To see the official certificate for a property, use the EPC checker.

Frequently asked questions

Is this an official EPC?

No. It is an estimate for planning improvements. Only an accredited domestic energy assessor can issue an EPC, which is lodged on the government register.

How long does an EPC last?

An EPC is valid for 10 years from the date it was issued, although you can get a new one sooner if you have made improvements.

What EPC rating does a rental property need?

In England and Wales, privately rented homes must currently have a rating of E or above unless a valid exemption is registered.