Energy Performance Certificate Guide
Everything you need to know about UK EPCs — what your rating means, how long it lasts, when you legally need one, and an instant estimate of what a new assessment will cost.
What Is an EPC?
An Energy Performance Certificate (EPC) rates how energy efficient a building is, from A (most efficient) to G (least efficient). It’s produced by an accredited Domestic Energy Assessor (DEA) after a short inspection of the property, and includes an estimate of typical energy costs alongside recommendations for cost-effective improvements.
📋 When You Need One
An EPC is a legal requirement whenever a property in the UK is built, sold, or let to new tenants. It must be commissioned before the property is marketed and made available free of charge to any prospective buyer or tenant.
⏳ How Long It Lasts
Once issued, an EPC remains valid for 10 years, regardless of who owns or occupies the property during that time. You only need a new one if the existing certificate expires, or if you want an updated rating after making efficiency improvements.
🔍 What the Assessment Covers
An assessor records details such as wall and loft insulation, glazing type, heating and hot water systems, and lighting. These factors are combined into a SAP (Standard Assessment Procedure) score, which determines the A–G rating band.
🛠️ Improving Your Rating
Common, cost-effective upgrades include topping up loft insulation, sealing draughts, switching to LED bulbs, and upgrading an old boiler. Larger projects like cavity wall insulation, double glazing, or solar panels can move a property up several bands.
Estimate Your EPC Cost
Enter a few details about your property to get an estimated price range for a new Energy Performance Certificate assessment from an accredited assessor.
Property Details
Tell us about the property being assessed
Cost Estimate
Indicative price range for your EPC assessment
EPC Rating Bands Explained
EPC ratings are grouped into seven bands based on SAP score, from most to least energy efficient.
| Band | SAP Score | Efficiency Level |
|---|---|---|
| A | 92 – 100 | Most efficient |
| B | 81 – 91 | Very efficient |
| C | 69 – 80 | Good / above average |
| D | 55 – 68 | Average (most common) |
| E | 39 – 54 | Below average |
| F | 21 – 38 | Poor |
| G | 1 – 20 | Least efficient |
EPC FAQ
Everything you need to know about Energy Performance Certificates.
An EPC is a document that rates a property’s energy efficiency on a scale from A (most efficient) to G (least efficient). It includes an estimate of energy costs and recommendations for improving efficiency.
An Energy Performance Certificate is valid for 10 years from the date it was issued. You do not need a new one during that period unless you make significant changes to the property or choose to update it.
In the UK, you are legally required to have a valid EPC if you are selling or renting out a property, or constructing a new building. It must be made available to prospective buyers or tenants free of charge.
Ratings of A or B are considered excellent, while C is generally seen as a good, above-average rating. The average EPC rating for homes in England and Wales is around D.
Common ways to improve an EPC rating include adding loft and cavity wall insulation, upgrading to double or triple glazing, installing a more efficient boiler, fitting LED lighting, and adding renewable measures such as solar panels.