All home sellers in England and Wales now need to prepare a Home Information Pack.

This pack must contain an Energy Performance Certificate on CO₂ emissions and energy efficiency for your dwelling.

Your choice of fire today will affect the future rating on your dwelling.

For this Certificate, you'll need to locate a Domestic Energy Assessor or a Home Inspector.

The measures are:

1. SAP rating, based on energy usage and adjusted for floor area, so it is essentially independent of dwelling size. This is scored from 1-100; the higher the number, the lower the running costs.

2. Environmental Impact Rating is based on the annual CO₂ emissions, and is expressed on a scale of 1-100. The higher the number, the lower the environmental impact.

3. Dwelling CO₂ Emissions Rate. This is expressed as CO₂ emissions per floor area in kg/m2, per year. See the table on Environment for CO₂ emissions for various fuels.