There are a number of measures that you can take to improve the Energy Performance Certificate rating of your property.
These include:
Lighting
Make sure you have plenty of energy saving light bulbs fitted. These are often on special offer, recently Tesco had 5 for 40p, that makes them cheaper than conventional bubs and the energy saving is considerable.
Hot water cylinder
Fit a hot water tank jacket or better still fit two, one on top of the other.
Loft Insulation
Installing new loft insulation in most properties is an easy DIY job and should be done to a depth of 270mm. See the Energy Saving Trust website for more details.
Wall insulation
Insulating your property properly is the most cost effective measure you can take. In most cases, cavity wall insulation is straightforward and inexpensive.
Central heating boiler
If your boiler is over 15 years old, it’s probably around 75%, or less, efficient and you might think about replacing it. Modern condensing boilers are over 90% efficient. A Combi boiler which heats the hot water as it is used will save even more energy.
Central heating controls
As a minimum the controls should include a programmer, a wall mounted thermostat and thermostatic radiator valves. If there is a hot water cylinder this should have a thermostat set at no more than 60°C, any higher is wasteful. There is a good page describing the workings of a Cental Heating system here.
Glazing
Double glazing reduces heat throught the glass and also reduces draughts.