Help reduce your energy bills by up to £160 a year[1]

Cavity walls are made of two layers with a small gap or ‘cavity’ between them which traps a layer of warm air between the bricks. By insulating the cavity you reduce the heat lost through your walls, which helps to keep your home warm. It’s a simple process, carried out by insulation experts, which could help you use less energy to heat your home and therefore reduce your heating bills.

How does cavity wall insulation work

Cavity wall insulation works by injecting insulation material into the cavity between the walls of your home. The insulation then acts as a blanket to help stop heat escaping through the walls of your home. It’s suitable for most homes built between the 1930s and the 1980s, is maintenance-free and comes with a 25-year guarantee from the Cavity Insulation Guarantee Agency (CIGA).

What does cavity wall insulation mean for your home?

Cavity wall insulation reduces heat loss through the walls and, as a result, provides an even temperature around your home. With less heat escaping, your home will be more energy efficient and your heating bills reduced. In fact, you could save around £160 per year.[1]

  • Takes less than a day to install.[2]
  • Keeps your home warmer in winter and cooler in summer.
  • Comes with a 25-year guarantee.
  • Saves you around £160 per year.[1]
  • Saves you around 600kg of CO2 per year.

Your installation journey

  • Prior to the visit, you’ll receive a call from the engineer to confirm the exact time of the installation.
  • All our engineers carry identification, so please feel free to ask to see it. The engineer will walk you through the process of the installation so that you know what to expect.
  • The engineers will drill small holes around 22mm wide in the mortar at intervals of one metre all around the outside of your home.
  • Insulation will then be blown into the cavity using specialist equipment.
  • Once all the insulation is in, the holes will be filled so you'll barely notice them.
  • After the installation is completed, you’ll be sent a 25-year guarantee from the Cavity Insulation Guarantee Agency (CIGA).

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[1] 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.

[2] British Gas install in mainland Great Britain only. Free installations are through the Energy Company Obligation and are subject to assessment, technical survey and eligibility criteria. The funding available is to cover insulation and if needed extra specialist equipment, i.e. scaffolding and vents. Some properties require more specialist equipment which can't always be covered so if you need more you have the option to pay the extra. Tenants must seek landlord's permission.