Free cavity wall insulation Wales

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Grants for free cavity wall insulation Wales

Homeowners and private tenants can now claim 100% grants for free cavity wall insulation in Wales.

Welsh families deemed to live in fuel poverty can now get government help to install free cavity wall insulation and loft insulation through the Energy Company Obligation (ECO) grant scheme.

The grant scheme is designed to reduce carbon emissions and help lower income households in Wales cope with the current energy crisis, and reduce the cost of heating their homes.

Insulating your home propely with cavity wall and roof insulation is still recognised as the easiest way to lower your heating bills quickly. Insulation acts as a thermal blanket on your property and prevents heat escaping from your home.

For many people in the private sector (homeowners, private tenants, and landlords), cavity wall insulation and solid wall insulation are currently free when installed with a free heat pump. If you reside in a council home, each Welsh government has its own policies to increase the housing stock’s energy efficiency.

Free Cavity Wall Insulation in Wales

Find out here if you are eligible for free cavity wall insulation via the ECO 4 grant scheme

What is cavity wall insulation?

Cavity insulation is installed by placing insulating material between the inner and outer layers of bricks in your walls. Modern insulation is waterproof and breathable.

As a result, less heat is transferred from your house to the outside. Your exterior walls allow more than a third of the heat inside your house to escape. Installing wall insulation can therefore result in significant energy cost savings.

Free cavity wall insulation in Wales

Is cavity insulation suitable  for my house?

In Wales, buildings constructed before the 1920s have sturdy brick or stone walls. If your house was built after this period, there’s a considerable likelihood that your house has a gap between the bricks of the exterior walls.

There aren’t many Welsh properties after this era that have solid walls. Our surveyors can verify this by making a small hole in your wall and using specialised equipment called a borescope to check inside.

Cavity wall insulation is typically an option for your home if:

  1. Your exterior walls are hollow walls with no filling.
  2. the brickwork is in good shape and the structure was constructed after the 1920s
  3. the cavity is at least 50 mm wide.

Cavity wall insulation helps reduce your energy bills because it keeps the heat in. Therefore you can turn down your central heating or run it for shorter periods of time. This lowers your heating expenses while lowering the amount of harmful emissions that are emitted into the atmosphere.

Additionally, the thermal barrier that cavity wall insulation provides, helps keep your home cooler in the summer months.

How can I tell if my home has cavity walls?

If your house was constructed before the 1920’s it will be built with solid stone or solid brick.  This is the period when cavity walls construction methods were introduced. There are several ways to tell if your property has cavity walls. The most obvious indicator is the type of  brick patterns on your walls.

The image below shows the type of brick patterns asssociated with both cavity and solid walls. If a wall is built with a cavity gap the bricks will all run the same way. In a wall of solid construction the bricks will be criss crossed. This indicates that there is no gap wetween the inner and outer leaf of bricks.


Cavity wall and solid wall brick pattern diagram

Why should I insulate my home?

Insulation that is effective keeps the heat inside your house, essentially covering your home in a thermal blanket. This makes it possible for you to keep your rooms at a more  comfortable and affordable temperature. Your boiler can be fired at a lower temperature or your central heating can be in use for less time throughout the day and night. This can lead to substantial savings

Your loft and roof also let out an additional 25% of the heat you generate with your boiler or heating system. This alone amounts to around 60% heat loss and means you are paying far more to heat your home than you should be.

Cavity Wall insulation

Cavity wall insulation prevents heat from escaping through your  walls. Specialist material is placed in the gap between your bricks. This sops heat escaping through your walls and helps lower your heating bills.

The average property in Wales loses about 35% of its heat through its exterior walls if they are not insulated correctly.

Solid Wall Insulation

If you live in a traditional or older stone built property you may need to insulate the walls with internal insulation. This type of property is constructed without a gap between the inner and outer bricks.

Internal solid wall insulation is an effective method of preventing heat loss. Insulation is placed in a frame on the inside of your wall then plastered.

This can be installed free of charge with an ECO grant, including all new plaster work.

Loft Insulation

Around 25% of the heat you generate with your boiler escapes through your attic or loft. Free loft insulation grants are available under ECO for Welsh households on benefits.

Room in Roof Insulation

If your property has rooms built into the roof it can still be insulated with specialist materials. The full cost will be covered with a government grant if you or a member of your household is eligible.

Heat loss in house that is not insulated

How do I apply for free cavity wall insulation in Wales?

Getting a free cavity wall insulation grant in Wales is an easy, no hassle process. In fact, you don’t even have to even apply for a grant. We do all the paperwork for you. We install the wall measure, then claim the money back from the energy companies. You don’t have to do anything.

  1. Simply provide us with your contact details and some basic information regarding your property and benefit status.
  2. We will arrange a home visit with an accredited energy assessor. The assessor will gather information about your property and assign an energy rating, similar to an EPC for a home report. This will include an inspection of your walls using a borescope camera.
  3. The assessor will then look at the energy efficiency of your property and provide a recommendation for wall insulation, if it is required.
  4. Your free cavity wall insulation will be installed, and we claim the money back from one of the utility companies in the ECO scheme.


How is the insulation installed?

Installing cavity wall insulation is much simpler than you may imagine. It takes about three hours to insulate a typical three-bedroom semi-detached house. The install project consists of several phases:


  1. House survey
    Before the work begins, a qualified surveyor will have come to your house to collect some measurements and photos. This will include a borescope inspection of your cavity walls. They will also sketch out a plan for the installation team. This will provide measurements and access details, indicate where your doors and windows are, and list any potential safety hazards.
  2. Drilling the holes
    Holes of around 1-inch-diameter are drilled into the mortar separating your bricks. No brickwork is drilled during this process.
  3. Installing the CWI
    The insulation will be blown into your walls at this location. The insulation installer has specialist instruments to ensure that your walls are completely filled, and there are no “cold spots.”
  4. Cleaning up
    The holes will be filled with mortar that matches your existing cement, and the work area will be thoroughly cleaned.
  5. Completion
    You will be prompted to “sign off” the installation if you are satisfied with it. You will receive a 25 year CIGA guarantee for the work shortly after it is finished.
    locating a certified installation of insulation.

What is the Energy Company Obligation?

ECO is a government-led energy efficiency program designed to help reduce energy bills and help meet the country meet net zero targets by cutting the amount of harmful emissions we release into the environment. The sheme is funded by medium and large utility companies who have a customer base in Wales. This includes British Gas, EON etc. The government has ruled that these companies have an obligation to help the most vulnerable households reduce energy costs by installing energy efficient measures like insulation, solar panels and air source heat pumps, free of charge.

The recent rise in energy prices means that more and more people are struggling with the cost of gas and electricity and find it difficult to heat their home properly. For some it is a choice between eating and heating. If at any time your household is facing this type of choice you are deemed to live in fuel poverty.

How is Fuel Poverty defined in Wales?

A household is deemed to be in fuel poverty if they can’ keep their home warm at a reasonable cost. This is measured as any household needing to pay more than 10% of their full household income to maintain satisfactory heat on a daily basis. Families who pay more than 20% of their full household income to maintain a satisfactory heating regime are deemed to live in severe fuel poverty. National Energy Action.

Check Eligibility

Find out if you are eligible for a free insulation grant in Wales

Who qualifies for a free cavity wall insulation grant in wales?

ECO grants are available for homeowners, private tenants in Wales who live in a property with a low energy rating of between E and G and are off the gas grid. Rural properties and properties heated by electric heaters, oil bloilers and LPG are often the least energy efficient. This type of property also often has the most room for improvement.

where a member of the household currently claims one of the following means tested government benefits:

  1. Universal Credit
  2. Child Tax Credits
  3. Working Tax Credits
  4. Income Support
  5. Income Based JSA
  6. Income Related ESA
  7. Housing Benefit
  8. Pension Savings Credit
  9. Pension Guarantee Credit

In addition to the above, families on a low income who claim basic child benefit may also be eligible if their total household income is below the following relevant thresholds:


  1 Child 2 Children 3 Children 4+ Children
Single Person £19,900 £24,800 £29,600 £34,500
Part of A Couple £27,500 £32,300 £37,200 £42,000

Free Insulation Grants in Wales

How do Wall  Insulation grants in Wales work?

Getting a free cavity wall insulation in Wales is easy. There is no complicated application or forms. If you are eligible and you live in a Welsh postcode area we do all the work for you.


Check your eligibility

Use our contact form to provide us with a few details about your property’s heating and construction.

Arrange a home survey

If you are eligible one of our accredited energy assessors will contact you to arrange a free  home survey.

Free Wall installation

We install your free cavity wall  insulation measure and claim the grant from the energy company. You don’t have to do anything.

Free cavity wall insulation in Wales – FAQ

01. Is my home suitable for cavity wall insulation?

Your home’s outside walls probably feature a double skin of bricks with a gap, or cavity, between them if it was built between the 1920s and 1990s. Prior to this time, houses were constructed from solid stone. Any houses constructed after this point are probably already equipped with insulation. Your home is not a good candidate for cavity wall insulation if it has solid walls or a timber or steel frame construction

02. How do I know if there is a cavity in my walls?

Cavity walls have different brick patterns from other types of wall constructions.
Also, by measuring the thickness of the wall close to the door, you may determine the sort of walls you have. You most likely have a cavity if it is 260mm or more.

Sometimes it is impossible to tell because your exterior walls may be rendered. Alternatively they may have been insulated at the time they were built.

Either way it is best to get one of our expert surveyors to come and carry out a borescope inspection to determine if the property has a cavity, and whether it is insulated or not.

03. What kind of material will be used to insulate my walls?

EPS polystyrene beads are now used to insulate cavity walls. It is an innovative, high performing solution used in both new build and retrofit insulation projects

Older materials like xpanding foam insulation and mineral wool are now not normally used for walls, especially in areas with extreme weather conditions.

04. Can I still get free loft / roof insulation?
If the insulation in your loft or attic is below the recommended depth of 270mm this can be topped up with mineral wool through the scheme. If your property has roofs built into the roof with dormer or velux windows the process is different. All stud walls, sloping walls and gables must also be insulated to prevent heat escaping.

Room-inroof insulation is similar to solid wall insulation. It can be fitted to the existing walls with strapping and then skimmed. The full cost of this will be covered with a grant.

5. Do I have to pay the grant back at any time in the future?
No. If you qualify for an isulation grant in Wales through the ECO scheme all funding is non-repayable. Even if you move home or your financial circumstances change it won’t cost you any money.

Free cavity wall insulation in Wales is available for homeowners and private tenants who claim an income-based benefit. Properties which are off the gas grid are given priority under the ECO4 grant scheme.

Are you eligible for a free cavity wall insulation grant in Wales?