Solid walls can also be insulated by applying wall insulation internally. Types include ready made insulation/silver backed plaster board, or wooden battens in-filled with insulation or flexible linings.
How does internal wall insulation work?
Insulation/plaster board laminates usually consist of plasterboard backed with insulating material typically to a total thickness of up to 90mm. The construction of the insulation reduces the amount of heat which would otherwise pass through into the wall and then outside.
How much can I save?
Internal wall insulation is cheaper than external wall insulation and you could save around £350 a year on your fuel bill. The savings for flexible insulating materials are lower, around £120 a year.
A three bedroom semi-detached house could save nearly 2.3 tonnes of CO2 a year.
How is it installed?
Costs for internal rigid wall insulation start from around £42 per square metre. The boards are fitted directly to the inside of the wall. The thicker the board is, the better the insulation properties. You can also attach wooden battens in-filled with insulation to a wall. This involves attaching battens to the wall, filling the spaces between the battens with insulation and then covering them over with a plasterboard.
Flexible insulating materials (a form of dry lining) can also be used. It is cheaper and can be bought in rolls like wallpaper which you can fit yourself. Typically a material like Sempatap Thermal can cost as little as £18 a square metre.
Other useful links