Home Energy Ratings

New build homes, are on average, more energy efficient than older properties. For example, a new home built to 2006 regulations will use an astounding 40% less energy than an equivalent home built in 2002.

There are two ways to measure a home’s energy rating:

  • Energy Performance Certificates (EPC)
  • Standard Assessment Procedure (SAP)

Energy Performance Certificates (EPC)


The EPC uses a home energy rating system to demonstrate the performance of a house on a scale from A (very efficient) to G (very inefficient). The format is very similar to that which is used for domestic appliances such as washing machines and dishwashers.

The home energy rating is based on a range of factors such as the age of the house, property layout, construction, heating, lighting and insulation. This is a standardised rating system so you can very easily compare one property with another.

The higher the rating, the more energy efficient the home is, and so the lower you can expect your fuel bills to be.

The average rating for a property is D/E, but if you have a new build home, the rating is more likely to be B or C.

Standard Assessment Procedure (SAP)

SAP is the government’s recommended system for measuring the efficiency of domestic properties in England and Wales.

A SAP calculation indicates a score on a scale between 1 and 100+ for a home’s annual energy cost, based on:

  • Structural elements
  • The heating and hot water systems used
  • Internal lighting
  • Renewable technologies used in the home

The higher the score the lower the running costs will be. A score of 100 represents zero energy costs. Dwellings with a rating in excess of 100 are net exporters of energy (e.g. those that have solar or PV panels and sell energy back to suppliers).

SAP and EPC scale


Below is an outline of how SAP ratings compare the EPC Scale:

Score Grade
1-20 G
21-38 F
39-54 E
55-68 D
69-80 C
81-91 B
92+ A

The average SAP rating for a property is 45. A new home should generally exceed 75.

Want to find out more about our commitment to energy efficient homes? Take a look at our Sustainable Living Brochure for more information.