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Stop wasting energy; start taking action! This is the section to get you started on energy-saving, whether it's changing your habits or improving your home – save energy and save money!
The better insulated your home is, the less money you'll spend heating it. Find out more about different types of insulation, including draught-proofing, double glazing, and insulation for lofts and walls.
The latest on energy-efficient boilers to save you energy and money, and the right controls to use as little energy as possible, whatever the age of your boiler. No boiler? Find out about controls for electric systems too.
Renewable and low-carbon technologies are good for the environment and good for your pocket too - with government financial incentives, it’s never been a better time to install. Find out more now!
Get inspiration for your own community projects from a range of case studies in PDF and video format; find extensive advice about funding your project; and explore our range of project tools.
If your home was built after 1920, the chances are that its external walls are made of two layers with a gap or cavity between them. Cavity wall insulation fills that gap, keeping the warmth in to save energy. It can also help reduce condensation inside the house if this is a problem on your external walls.
Not sure whether you have cavity walls? Work out what sort of walls you have.
Carbon dioxide saving per year
|Cavity wall insulation||Up to £140||£450 to £500||Under 4 years||Around 560kg|
These are estimated figures based on insulating a gas-heated, semi-detached home with three bedrooms. The average installed cost is unsubsidised.
Your home will usually be suitable for cavity wall insulation if:
If your house was built in the last ten years or so, its walls are probably insulated already. To find out whether they are:
Cavity wall insulation is blown into the cavity from the outside of a house. Every part of the wall must be filled with insulation, so it's important that the installer can reach all your external walls.
If your home's external walls are joined to another house, the installer will need to insert a cavity barrier to contain the insulation, so your neighbours aren't affected.
If you have any damp patches on your internal walls then they should not be insulated until the problem is sorted out. You should speak to a builder who specialises in damp prevention.
To insulate your cavity walls, the installer drills small holes around 22mm in size at intervals of around 1m in the outside wall of your home. With specially designed equipment, they then blow insulation into the cavity. Once all the insulation is in, the installer fills the holes in the brickwork so you'll barely notice them.
Filling cavity walls is not a job you can do yourself: you will need to find a registered installer. A professional can do the job in around two hours for an average house with easily accessible walls; it should be simple, quick - and make no mess.
Your installer should be a member of one of these organisations:
Remember to also check that:
Cavity wall insulation can be made out of three types of materials:
All three are manufactured according to British standards. Foam Insulation systems should be certified by the British Board of Agrément and installed according to strict guidance laid out in the associated BBA Certificates.
Your installer will suggest the most suitable type of insulation for you but ask if they are using Energy Saving Trust Recommended insulation: this means it complies to British standards and it has a 25-year guarantee. Energy Saving Trust Recommended cavity wall insulation is the most energy efficient on the market so will save you money and energy. Ask your installer to look for the label to make sure you make the best choice.
Until April 2015, the Landlord’s Energy Saving Allowance lets you claim up to £1,500 against tax for energy-saving improvements you have made to each house or flat you rent out. Find out more at the Directgov website.
You’ll be charged a lower rate of VAT when you have energy-saving work done to your house, both for the materials and equipment, and for the labour. If the house is new, you pay no VAT at all. Find out more at the HMRC website.