Home > Grants & Funds > Cavity Wall Insulation

Cavity Wall Insulation

By: Scott McBride - Updated: 15 Dec 2020 | comments*Discuss
 
Cavity Wall Insulation Energy Heat

Mind the Gap

Cavity wall insulation is big business. Between 2002 and 2005 it was installed in around 800000 UK homes, reducing harmful carbon dioxide emissions by 400,000 tonnes. But the energy wasted by homes without cavity wall insulation is still considerable - enough to heat 1.4 million homes every year.

The average home's energy bills can be cut by 15 per cent by cavity wall insulation, which reduces the amount of heat lost from the property by filling the gap between the two external walls of a house with an insulating material. Cavity wall insulation is not suitable for all homes, but it is for most built after the 1920s. That is because the exterior walls of these properties are typically made of two layers with a cavity between them.

It is relatively cheap to install, costing around £500 for a three-bedroom semi-detached house and reduced bills will mean it pays for itself within six years. There is not much mess, as the insulating material is injected into the cavity through small holes drilled in the wall - usually from the outside. The whole job can be completed within three hours by trained technicians.

The three most common types of cavity wall insulation are:

  • Polystyrene beads or granules - blown into the wall cavity using compressed air.
  • Urea formaldehyde foam - formed in the wall cavity by injecting and mixing two chemicals. The foam expands to fill the cavity.
  • Blown mineral fibre - made of mineral wool or fibreglass that is forced into the wall cavity using compressed air.

Homes without insulation lose about a third of their heat through the walls, and insulation has other benefits. It creates a more even temperature in the home, can keep the home cooler during hot spells in the summer and helps prevent condensation on walls and ceilings.

There are options for homes that are not suitable for cavity wall insulation. Solid walls lose more heat than cavity walls, but insulation on the inside or outside can reduce energy loss. External insulation needs to be between five and 10 centimetres thick and the weather-proof treatment can cost around nine times that of cavity wall insulation. Interior insulation typically consists of plasterboard backed with insulating material and is around nine centimetres thick. It can be as effective as exterior insulation and costs far less, starting at less than £50 per square metre. Flexible insulating lining, which comes in rolls like wallpaper, can also be used for interiors and is easy to fit. It is cheaper but far less effective and energy savings will be less than a third of those made by the other forms of wall insulation.

Cut the Cost with a Grant

Grant assistance for installing cavity wall insulation is available through the Government, energy suppliers and local authorities. Most local authorities offer grants and incentives to residents installing energy-efficient measures in their homes, while the biggest energy suppliers are obliged to meet targets under the Government's Energy Efficiency Commitment. Government funds provide grants, although the eligibility criteria differ between countries. The funds are called Warm Front in England, Warm Deal and the Central Heating Programme in Scotland, Warm Homes in Northern Ireland and the Home Energy Efficiency Scheme in Wales.

Those who own their home or rent it from a private landlord may be eligible for a grant to cover between 30 and 70 per cent of the cost of cavity wall insulation, while those in receipt of an income or disability benefit could be entitled to free cavity wall insulation.

You might also like...
Share Your Story, Join the Discussion or Seek Advice..
I have just purchased a barn with pdq, that i would like to replace with eco friendly new build. Could you please advise me on what grants are available to me and how I apply. The site is in Devon
Flacky - 15-Dec-20 @ 8:57 PM
Hi, I own Near Howe Cottages (7 self catering cottages in Mungrisdale Cumbria - North Lakes) and am looking for advice on any grant aid available to install Cavity Wall Insulation in 3 of our single story cottages. I am also after advice on which companies to approach for quotations, as you hear some real horror stories re cowboys in this sector. I look forward to hearing your response? Warm Regards Steve Woolley
Steve Woolley - 31-Oct-18 @ 1:39 PM
Hi, I am looking for some informations regarding grants for a new build in rural aberdeenshire. We are looking at putting underground source heating in and wonder what grants are available for this if any?
Lornafiona - 17-Jan-14 @ 8:34 PM
Share Your Story, Join the Discussion or Seek Advice...
Title:
(never shown)
Firstname:
(never shown)
Surname:
(never shown)
Email:
(never shown)
Nickname:
(shown)
Comment:
Validate:
Enter word:
Topics
Latest Comments
  • Dudz
    Re: Grants Available For Your Business
    I run a small social club, non profit making run by volunteers. The Building consists of two bar areas back to back and a…
    9 August 2022
  • Char K
    Re: New Build Grants and Funds
    Hi there, We have recently bought a house that needs a complete update. We have our plans approved to extend and renovate fully and…
    29 July 2022
  • Spence
    Re: New Build Grants and Funds
    Hi We have class q planning to convert a barn into a dwelling in the countryside in Devon, are they any grants available to us???
    13 June 2022
  • Doug
    Re: New Build Grants and Funds
    Please contact me asap
    4 June 2022
  • Franco
    Re: New Build Grants and Funds
    I am about to develop a brownfield site into 11 dwellings and wonder what grants might be available to assist me in reducing the…
    6 May 2022
  • PP PP PP PP PP PP PP
    Re: Eco-School Grants and Funds
    PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP PP…
    28 March 2022
  • IXL IS SHIT
    Re: Eco-School Grants and Funds
    This app is bullshi* and the cun* that made this should die This is absolute bullshi* and the retar* that made this crap can go to…
    27 March 2022
  • Rossco
    Re: New Build Grants and Funds
    Hi iam hoping to be granted planning permission for a self build in November. The plot will be in a 5 acre plot on the outside our…
    2 October 2021
  • AMS7
    Re: Grants Available For Your Business
    My company currently operates from a small workshop space with corrugated roof and no ceiling, looking at foam insulation…
    6 September 2021
  • sludgebuster
    Re: Are There Any Grants for Water Treatment Systems?
    I live in a barn that was once part of a farm and found out yesterday that our outlet for drainage (we…
    6 September 2021