What is cavity wall insulation?

Views of cavity wall insulation from the side and from the top.

Cavity wall insulation is a filling blown into the gap between your interior and exterior walls. It helps prevent heat escaping through the cavity walls of your home. Without cavity wall insulation you could be wasting as much as £160[2] every single year.

It keeps your home warmer in winter and cooler in summer.

You don't need to be a British Gas customer to get free insulation.

If your home was built between 1932 and 1982 then you are likely to have cavity walls.

Any home built after 1st January 1983 should already have cavity wall insulation installed.

Benefits of cavity wall insulation

  • Save up to £160[2] every year on your energy bills.
  • It’s quick and usually takes less than a day.
  • Convenient, hassle free installation and we tidy up after.
  • Reduce heat loss – up to 35% of heat is lost through uninsulated walls.
  • Save around 600kg of CO2 every year, reducing the impact on the environment.

[1] There are a few areas of the country we can’t reach, to check if you live in one of them just give us a call. Modern houses are built with insulation, so houses built after 1991 will already have loft insulation and houses built after 1983 will already have cavity wall insulation. We give free insulation under the Energy Companies Obligation and we’ll need to do a survey to make sure your house qualifies. We’ll cover the cost of the insulation itself, but if your house needs specialist equipment or scaffolding, you may need to contribute to the cost. If you rent your house, you’ll need your landlord’s written permission.

[2] Savings figure source energysavingtrust.org.uk/Insulation/Roof-and-loft-insulation and energysavingtrust.org.uk/Insulation/Cavity-wall-insulation March 2015. Actual savings depend on individual circumstances.