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Cavity Wall Insulation

Cavity wall insulation will significantly reduce the amount of energy you need to heat your home. The average house could reduce heating costs by over a third.

In most houses built after the 1920s, the external walls are made of two layers with a small air gap or 'cavity' between them. If your home has unfilled cavity walls, a considerable slice of your energy bills will be spent heating the air outside.

Filling the gap between the two walls of a house with an insulating material massively decreases the amount of heat which escapes through the walls. It will help create a more even temperature in your home, help prevent condensation on the walls and ceilings and can also reduce the amount of heat building up inside your home during summer hot spells.

Around a third of all the heat lost in an un-insulated home is lost through the walls. If you have cavity walls, insulating them will make a great difference, and it could save you up to £480 a year on your fuel bills.

For more on how cavity wall insulation works, costs, savings and other considerations see the Energy Saving Trust information page1.

View information on the planning and building regulations regimes covering insulation in our common projects section2.


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Useful links

Make an application Planning consultancy calculator
    1. https://www.energysavingtrust.org.uk/home-insulation/cavity-wall
    2. https://www.planningportal.co.uk/permission/common-projects/insulation
    3. https://ciga.co.uk/
    4. https://www.nia-uk.org/
    5. https://www.bbacerts.co.uk/

    The Planning Portal is delivered by PortalPlanQuest Limited which is a joint venture between TerraQuest Solutions Limited and the Department for Levelling Up, Housing and Communities (DLUHC). All content © 2024 Planning Portal.

    The Planning Portal is delivered by PortalPlanQuest Limited which is a joint venture between TerraQuest Solutions Limited and the Department for Levelling Up, Housing and Communities (DLUHC). All content © 2024 Planning Portal.