Solid wall insulation is highly effective at keeping you warm and saving you money on heating. It is not, however, cheap to install. That is why the UK government offers free insulation grants to help pay for it—at times even the full amount.
Here is everything you need to know regarding solid wall insulation grants. We will tell you how it works, who is qualified, how much it pays out, and how it will save you money and keep you warm.
If your home is built of solid walls and is cold in winter, this guide is for you.
What is Solid Wall Insulation?
Solid wall insulation is a way of stopping the loss of heat through your walls. It is an extra layer of insulation on the inside or the outside of your property. It stops the loss of the heat inside your home in winter and keeps unwanted heat out of your home in the summer.
There are two types of solid wall insulation:
External Wall Insulation
- The exterior of the wall is clad with insulating boards or materials.
- It is covered with a protective covering, i.e. render or cladding.
- It improves the insulation and also changes the look of your home.
- Also, it is suitable for houses with brick or stone exterior walls.
Internal Wall Insulation
- Studs or insulation boards are placed inside your home.
- It minimises heat loss without altering the exterior.
- It is perfect for homes within conservation areas where exterior alteration is prohibited.
- Both types of insulation make your home warmer, energy-efficient, and cheaper to heat.
Why Do Certain Houses Need Solid Wall Insulation?
The majority of older homes in the UK, especially those built before 1930, have solid walls rather than cavity walls. Solid walls, in comparison to modern walls, don’t have a cavity filled with insulation. They hence lose more heat.
If your property has solid walls, you could:
- Spend extra money on heating since it loses heat rapidly.
- Feel colder in winter even when the heating is on.
- Have high carbon emissions, making your home less eco-friendly.
Solid-wall insulation is effective in reducing the amount of heat lost by up to 45%, heating your property, keeping it warm, and lowering your energy bill.
How Much Can You Save?
Solid wall insulation will pay you a lot of money in the long run. According to 2025 projections:
- A mid-terrace property will set you back between £300–£400 per annum
- A detached property is capable of saving up to £600 per annum.
Your home will feel warmer, and your heating system will not be working as hard.
What is a Solid Wall Insulation Grant?
Exterior solid wall insulation is expensive, costing between £7,000 and £15,000. To help with the cost, the UK government offers grants under initiatives such as:
ECO4 Scheme (Energy Company Obligation)
- Supported by energy companies to help low-income families.
- Pays the full cost of the insulation on qualified homes.
- Targets homes with low energy efficiency ratings (E, F, or G).
- You may be qualified if you receive benefits like Universal Credit or Pension Credit.
Great British Insulation Scheme
- Helps low energy efficiency households.
- Partially pays for the installation of insulation.
- Available to everyone, not just to recipients of benefits.
Local Authority Grants
- Some councils provide additional funding to provide home insulation.
- They are usually directed toward low-income and fuel-poverty households.
If you qualify, the grants will cover much of the insulation or even all of it, and you will be saving on your energy bill.
What is the ECO4 Scheme?
ECO4 is a scheme that helps low-income households improve the efficiency of their homes. It runs until March 2026.
If you qualify, the scheme will provide:
- Loft Insulation
- Cavity wall insulation
- Solid wall insulation
- New boilers
- First-time central heating
- Smart heating controls
The objective is to decrease fuel poverty and carbon emissions. Your home should be energy inefficient and you should be qualified.
Who is Eligible for a Solid Wall Insulation Grant?
You might qualify if:
- You own or privately rent your own home.
- Homeowners can apply directly
- Private tenants must obtain permission from the landlord
- Council and housing association homes might have specific schemes
- You get certain benefits
- You usually qualify if you receive:
- Universal Credit
- Pension Credit
- Child Tax Credit
- Working Tax Credit
- Income Support
- Jobseeker’s Allowance (JSA)
- Employment and Support Allowance (ESA)
If you don’t qualify for any benefits, you may still be covered under the Great British Insulation Scheme, but you could be required to pay towards the cost.
- Your building has a low EPC rating.
- Your home is energy inefficient and has a low EPC rating of E, F, or G.
How Do You Apply?
Here is how it usually goes:
Step 1: Check Your Eligibility
You can fill out an online application with a qualified installer. They will ask you to provide:
- Postcode
- Property type
- Heating system
Step 2: Schedule a Free Survey
If you seem qualified, they will send you a free home survey. This confirms:
- Type of wall (solid or cavity)
- EPC rating
- Heat loss
- Current heating system
Step 3: Get Approved
If you meet the requirements, they apply on your behalf. No paperwork to complete.
Step 4: Installation
Once approved, trained installers install the insulation. They do so in:
- 1–2 weeks for external wall insulation
- 3–5 days of interior insulation
- Everything is done to government standards.
If the grant covers 100% of the amount, you don’t have to pay anything. If not, you might be asked to make a minimal contribution.
Is It Worth It?
Certainly. Insulating solid walls is one of the best ways of saving money and increasing comfort. If you have no insulation, you lose a lot of heat through the walls. That’s money being wasted.
Through a grant, you can have it done free of charge or at a very low fee. It is a long-term investment with short-term payouts.
The Bottom Line
Solid wall grants are having a big impact in the UK in 2025. It is now possible for older homes to be healthier, warmer, and less expensive to run.
If you have a solid-walled property and you find it cold in winter, it’s worth discovering whether you qualify. With ECO4 and LA Flex, free or highly discounted insulation is provided to millions of homes.
It is simple to apply, the money you save is real, and the result is permanent. You will be consuming less energy and being snug all year round.
Don’t lose your heating through the walls. You could keep it where it needs to be—in your own home—with a free grant.
