25 Year Guarantee

Free Cavity Wall Insulation

Since 2003, we’re the UK’s leading cavity wall insulation grants provider – trusted by over 500,000 happy customers

Get Free Cavity Wall Insulation For Your Home

We have government-backed funding available for a 100% free cavity wall insulation grant for your home. Over 5 million UK homes are already enjoying the benefits of an insulation grant.

Our cavity wall insulation will significantly improve the thermal, acoustic and energy efficiency in your home, meeting the latest building regulations – it’s like a giant blanket for your home.

You are entitled to our 100% free cavity wall insulation grant if you’re a homeowner or privately rent your property, regardless of your age, savings, property size or heating type – you won’t pay a penny – subject to a free survey.

If your home was built between 1920 and 1990, it is likely to have cavity walls that are not insulated. Properties built after 1990 will be insulated at the point of the build, in line with building regulations.

A cavity wall is made up of two walls with a gap in between, known as the cavity; the outer leaf is made of brick and the inner layer of brick or concrete block where insulation is injected.

What are these beads?

These beads are simply tiny spheres of polystyrene that are 98% air. It’s this air that gives the beads their outstanding thermal properties.

Benefits of our cavity wall insulation:

And Remember…

It will help to keep your home warm in the winter and cool in the summer.

Our customers are important to us…

That’s why we work hard to make sure that our service is as quick, easy and to the highest standard

A 25-year Cavity Insulation Guarantee covers our work

Step 1 of 4

To get your free survey, enter your postcode below:

I'm Interested In

  • Fast free survey
  • Certified national installer
  • Save money on energy bills
  • 14 days completion plan
We never share your information.
Step 2 of 4

Property Details

Step 3 of 4

We may be able to offer additional free grants such as free boiler, free solar if you or anybody in your home are in receipt of one or more of the following benefits:

Step 4 of 4

Please fill in the form and our friendly grant team will call you within 24 hours to book your free survey

Something has gone wrong, please try again later.
Thank You For Your Enquiry
Data Protection Act 1998 Reference: Z283974X

4 Easy Steps To Get Free Insulation

Complete the short 60-second form or call our friendly UK team 24/7 free on 0800 612 7878. We’ll take your name, address, best number to call and a few property questions

One of our grant staff will then call you back within 1 hour and book your free survey on a convenient date and time

Our qualified assessor will attend, survey your property and advise you of your options

Installation is usually within 14 days. That’s it! – you get a warmer home and lower bills

Cavity Wall

If you can see the brickwork on the outside of the house, look at the pattern of the bricks. If your home has cavity walls, the bricks will have a regular pattern – full brick lengths visible and have a cavity in between the two walls where insulation can be injected.

If your wall looks like this you may be eligible for a grant

Solid Wall

Solid walls typically have a combination of bricks ends and lengths – the bricks will have an alternating pattern.

 There is no space to inject insulation into these walls.

Please note; we do not install external wall insulation.

Wall No v2

If your wall looks like this you will not be eligible for a grant

Contact Keep Warm's friendly staff

About Us

With over 100 staff nationwide, you can be assured that our experienced and highly skilled team will do a great job; helping you through the process from your initial enquiry to installation – leaving your home as tidy as when they arrived.

For your safety and security, all our teams are fully CRB vetted and wear/display their photo identity badges at all times whilst on duty.

Our installation team are more than just experts

Of course, you want someone who is certified to install your insulation. But you also want someone who is friendly, who listens, who answers your questions and who keeps your home neat and tidy. Our expert staff never forget that they are people first and installers second.

Since 2003 we’ve helped over 500,000 people save money on their energy bills

We are proud that over 500,000 UK homes have trusted us to help them with their home insulation; saving money on expensive energy bills and making their homes warmer.


What our customers say...

“The house is now much warmer thanks to a neat good job done by the workmen. No mess and very little noise.”
T A Moseley

“Thank you for the speedy and efficient service. The work was completely quickly without mess.”

S Cartney

“Just to let you know that I was very impressed with the job your workmen did installing my home insulation. They worked quickly and were very respectful when they needed to come through the house. The standard of service and workmanship was excellent.”
W Wright

This is a government energy efficiency scheme to help reduce carbon emissions and tackle the cost of energy


How long will it take to carry out the installation?
Most properties take around 2-3 hours. 

How long does cavity wall insulation last?
For the lifetime of the building.

What type of material do you install?
Our teams use EPS beads, which are tiny spheres of polystyrene that are 98% air. It’s this air that gives the beads their outstanding thermal properties.

EPS beads are the best material for cavity wall insulation. They are more thermally efficient and long-lasting than any other product.

EPS beads do not deteriorate and, because of their shape, allow water to flow downwards. Therefore, any moisture that does enter the cavity after the beads have been installed will simply drain away to the ground. (If fibre insulation gets wet it will act like a sponge, drawing the water across the cavity and holding it against your walls).

Is the cavity wall insulation guaranteed?

Yes – a Guarantee is provided by CIGA (Cavity Insulation Guarantee Agency) – this is a 25-year guarantee and applies to the property, not the person, so you need to keep it safe with other documents for your property. You will need this document if you sell your house. We will apply for the Guarantee on your behalf.

Are all houses suitable for cavity wall insulation?

No. If the house is not of traditional construction and was built before 1920, it is unlikely to be suitable. The following types of property are also not suitable for cavity fill: timber frame, steel frame, and random stone.

My house is semi detached / terraced, will the cavity wall material go into my neighbour’s walls?

No – if the neighbour’s house is already insulated then our material will stop where it meets theirs. If it is not already insulated, our installers will fit a cavity barrier at the party wall line, usually made from bristle brush. This will prevent any trespass of material.

Book Your Free Survey…

Complete our 60second short form or call our friendly UK team 24 hours, 7 days a week free on 0800 612 7878 and our grant staff will book your free survey at a convenient time and date.