Energy Performance Certificate and the Asset Rating

CONTENTS

Energy Performance Certificate and the Asset Rating

For every building requiring an Energy Performance Certificate (EPC) the crucial outcome is the asset rating which reflects the potential energy efficiency of a building. The asset rating is the 'design' rating of a building reflected by the CO2 emissions of a building's design features on an A to G scale.

The asset rating is defined by the national calculation methodology (NCM). Using an approved calculation tool, your assessor creates a model of the annual CO2 emissions from the building.

The model takes into account the following factors:

  • The thermal characteristics of the building (thermal elements and controlled fittings as an envelope) including the air permeability.
  • The efficiency of the heating installation and hot water supply, including their insulation method.
  • The efficiency of the air-conditioning installation where installed.
  • The ventilation strategy, accounting for natural and mechanical means.
  • The artificial built-in lighting installation efficiency.
  • The position and orientation of buildings, including the weather location.
  • The use of passive solar systems and solar protection to reduce the need for cooling.
  • The indoor climatic conditions, including the designed indoor climate.
  • The activity of the building

Further reading

‘Improving the energy efficiency of our buildings: A guide to energy performance certificates for the construction, sale and let of non-dwellings' available from www.communities.gov.uk