£7,500 GRANT AVAILABLE FROM 
Cavity Wall Insulation Savings Calculator UK
Wondering how much you could save by insulating your cavity walls? Use our quick calculator to get an instant estimate based on your property type, heating fuel, and benefit status.
It’s fast, simple, and will show you how much money you could be keeping in your pocket every year.
Check If You Qualify
Your information is kept confidential and secure
Cavity Wall Insulation Savings Calculator
Select Property Type:
Select Fuel Type:
Do You Receive Benefits?
How Much Can I Save with Cavity Wall Insulation?
Your exact savings depend on your home’s size and how you heat it. On average, UK households can expect:
| Property Type | Typical Annual Savings |
|---|---|
| Detached House | Up to £455 |
| Semi-Detached House | Around £270 |
| Mid-Terrace House | Around £180 |
| End-Terrace House | Around £230 |
| Flat / Maisonette | £130–160 |
| Bungalow | Around £250 |
💡 Electric or oil-heated homes may save even more, due to higher fuel costs.
These are realistic estimates based on current UK fuel prices and standard property heat loss. Your savings start immediately after installation — and continue for decades.
What Is Cavity Wall Insulation?
Cavity wall insulation fills the gap between your property’s inner and outer brick walls with energy-saving material — usually mineral wool or polystyrene beads. This stops heat escaping and helps your home stay warmer for longer.
Benefits:
Cut energy usage by up to 35%
Improve indoor comfort all year round
Reduce carbon emissions
Increase your EPC rating (required for selling or renting)
May boost property value
May qualify you for government insulation grants
Can I Get Free Cavity Wall Insulation?
Yes — you may be able to get your cavity walls insulated entirely free of charge through either the ECO4 or GBIS government schemes.
You’re likely eligible if:
You receive income-related benefits
OR you are in Council Tax Band A–D in England, or A–E in Scotland
You own or privately rent the property (with landlord permission)
Not sure about your Council Tax Band or EPC rating? Our team can check that for you as part of your grant application.
What’s Next After Using the Calculator?
Once you’ve seen how much you could save:
Visit our Insulation Grants page to check full grant eligibility
Fill in the quick form to begin your free home survey
If you qualify, we’ll arrange your grant paperwork and installation — at no cost
Our team at HNR Energy Solutions will guide you through every step — from assessment to insulation — with zero pressure and no hidden fees.
Common Questions About Cavity Wall Insulation
Is cavity wall insulation worth it?
Yes — with savings of up to £455/year and grants covering the cost, it’s one of the most effective energy-saving upgrades for UK homes.
How do I know if I already have cavity wall insulation?
Check your EPC certificate, ask your installer, or book a free survey with us.
Can I get cavity wall insulation if I’m not on benefits?
Yes, under the GBIS scheme, homeowners and tenants not on benefits can still qualify — especially if they’re in a lower council tax band or have poor EPC ratings.
Is there any cost at all?
In most cases, cavity wall insulation is completely free through ECO4 or GBIS. We’ll confirm during the survey.
Start Saving Today
Insulating your cavity walls can help lower your heating bills, make your home cosier, and protect against rising energy costs — all while reducing carbon emissions.
Use the calculator above to check your savings, then get your free insulation grant assessment here.