Domestic Energy Assessments are undertaken on existing dwellings by a qualified inspector who has been trained to collect the correct information about the energy efficiency of your home. This information is then processed by a Government-approved organisation to produce the energy rating for the dwelling.

Using SAP to measure efficiency

The ratings provide you with a measure of the overall energy efficiency of your home and its environmental impact. Both are calculated using the Standard Assessment Procedure (SAP), which is the Government’s recommended system for assessing the energy efficiency of dwellings. The ratings take into account the home’s insulation, heating systems, hot water system, fixed lighting, ventilation, number of windows and related fuels.

How are the energy ratings calculated?

Not all of us use our homes in the same way so to allow one home to be directly compared to another, energy ratings are calculated using ‘standard occupancy’ assumptions. Standard occupancy assumes that the house is heated for nine hours a day during weekdays and 16 hours a day at weekends, with the living room heated to 21 degrees centigrade and the rest of the house at 18 degrees centigrade.

The ratings are expressed on a scale of 1 to 100. The higher the energy efficiency rating the more energy efficient the home and the higher the environmental impact rating the less impact it has on the environment.

Homes which are more energy efficient use less energy, saving money and helping to protect the environment. A home with an energy efficiency of 100 would be energy self sufficient and so the cost of proving lighting, heating and hot water would be practically zero.

Click the link below to view a sample EPC. The link requires Adobe Acrobat Reader to be installed (a well-established web format). Click the "Get Adobe Reader" icon below to install the latest version...

Sample Energy Performance Certificate (PDF, 186Kb)