A brief guide to improvement measures
An EPC will make recommendations for improvement based on the data your Energy Asessor inputs to the EPC. The Energy Saving Trust is a valuable resource for guides on each measure, but here is a brief rundown of the most common measures:
Internal wall insulation: Suitable for solid brick walls, the EPC software accepts 50mm or more. Insulation can take different forms, either solid board, rock wool or insulated plasterboard, which is essentially plasterboard with rigid board insulation tuck to it.
External wall insulation: This is usually a layer polystyrene covered in render. The benefit is that you don’t lose any internal space inside the dwelling, but it changes te external look of the property.
Cavity wall insulation: When cavity walls were introduced they initially were unfilled. Later cavities were filled with insulation and older walls can have insulation retrofitted, this will be pumped into the cavity via boreholes.
Loft insulation: One of the easiest, most effective and more popular improvements. Either rolls of rock wool, or solid board insulation. More commonly fitted at Joist level but can be fitted to rafters. Modern properties are fitted wiith 270mm.
Solid floor insulation - If a floor needs replacing anyway, rigid board insulation can be laid and the concrete re-laid on top, however for retro-fitting an existing floor it is more likely the insulation would be laid on top. This will raise the floor level, requiring you to cut doors down.
Suspended timber floor insulation - This involves pulling up the floorboards to insert insulation on the underside, usually held in by nets.
Double glazed windows - Provide a big improvement over single glazed windows. Windows installed after 2002 have a further gain over widnows before this period due to changes in specification at this time. Existing timber framed single glazed windows can be draught-proofed as a cost effective measure.
Low Energy Lighting - The easiest and most popular way to save electricity. Replacing old lightbulbs with modern low energy lighting can be done by the homeowner and will make a small improvement to the EPC rating.
Space heating - older boilers can be replaced with modern, condensing boilers. This will make a huge difference to the EPC, especially if replacing electric heating such as panel heaters. If heating controls aren;t present then this will often will be recommended, such as a thermostat/programmer and TRV’s on the radiators (thermostatic radiator valves).
Water heating - Water tanks can be insulated to reduce heat wastage, and if there isn’t a thermostat on the tank (telling the boiler to turn off when the water reaches temperature) then this will usually be recommended. If installing a combi boiler this will make a big improvement over electric immersion heaters.
Solar water heating - Use the sun’s energy to heat water which is then fed into a water cylinder. They usually affect the EPC rating in a fairly small way, as they can’t usually provide 100% of the hot water required you will also need another form of heating water.
Solar panels - A big win on the EPC but an expensive up-front cost. Solar PV will generate electricity and lower bills, and you can sell the excess to the grid or store in a batter for use later.
Wind turbine - only suitable for rural areas and can create issues with noise.
When considering any improvement measure, always consult a qualified professional. Some measures are unsuitable for some properties, and there may be other issues to consider, such as ventilation if you are installing additional insulation.