Cavity Wall Insulation

Keeping your home warm requires keeping the heat where you need it – inside! If your home is built with cavity walls, where there are two walls (inner and outer) with a gap in between, you may be able to insulate this gap to keep heat in.


Benefits of cavity wall insulation

Around a third of all heat loss in an uninsulated home is through the walls. By insulating your wall cavity you will help you reduce heat loss, reduce your bills and lower your carbon footprint.

According to the Energy Saving Trust, a typical semi-detached home could save around £395 by insulating their cavity wall.


Is it suitable for my home?

Homes built after the 1920s and before the 1990s are likely to have a cavity that can be insulated. The cavity will need to be unfilled and be at least 35mm wide.

If your home has solid walls, cavity wall insulation will not be appropriate.



If the brickwork has been covered you may be able to measure the width of the wall at a door or window. If the width of the wall is narrower than 260mm thick it is likely to be a solid wall.

If your house is steel or timber framed or made from pre-fabricated concrete, you will need to speak specialist advice to see if any insulation can be carried out.

Your walls will also need to be in good condition.


Things to consider

Ventilation – You will need to ensure your home is adequately ventilated once cavity wall insulation is installed.

Dampness – If your home has issues with rising or penetrating damp, you should seek advice before going ahead with a cavity wall insulation installation.

Cavity wall insulation should be guaranteed for 25 years by CIGA.


Help with the cost of insulation

You may be eligible for support with the cost of insulating your home if you live in Scotland.

You can contact Home Energy Scotland (HES) on 0808 808 2282 to enquire as to what support is available. You can also contact our advisors who can provide free and impartial advice and make referrals to HES on your behalf.


Support from Cosy Kingdom

Do you need more advice on insulation? Our energy advisors are always happy to help.

Our energy advisors can be contacted by:

Calling 01592 807930

Texting COSY then YOUR NAME to 88440


Through our website

Or on our Facebook and Twitter social media pages.