Cavity Wall Insulation Cost Calculator 2025
Calculate the cost of cavity wall insulation for your home. See full price vs. grant-funded costs with ECO4 and GBIS schemes.
Calculate Your Cavity Wall Insulation Cost
You may qualify for government grants!
With an EPC rating of D, you could be eligible for ECO4 or GBIS funding if you receive benefits or earn under £36,000/year.
Ready to Check Your Grant Eligibility?
Find out if you qualify for free or heavily subsidized cavity wall insulation
Check Eligibility & Get Free QuoteWhat is Cavity Wall Insulation?
Cavity wall insulation involves filling the gap between the inner and outer walls of your home with insulating material. This dramatically reduces heat loss and can cut your energy bills by up to 35%.
Most UK homes built between 1920 and 1990 have cavity walls - two layers of brick or block with a gap (cavity) between them. If your home has cavity walls that aren't insulated, you're losing significant amounts of heat through your walls.
Cavity Wall Insulation Cost Breakdown 2025
Typical Semi-Detached House
Average cost: £725 - £950
Installation time: 2-3 hours
Detached House
Average cost: £1,200 - £1,600
Installation time: 3-4 hours
Terraced House
Average cost: £475 - £650
Installation time: 1.5-2 hours
Bungalow
Average cost: £550 - £850
Installation time: 2-3 hours
Note: These are full commercial prices. With ECO4 or GBIS grants, eligible homeowners can get cavity wall insulation installed for free or at a heavily subsidized cost.
Government Grants for Cavity Wall Insulation
ECO4 Scheme
The Energy Company Obligation (ECO4) scheme can cover 100% of cavity wall insulation costs for eligible homeowners.
Great British Insulation Scheme (GBIS)
GBIS provides funding specifically for insulation measures, including cavity wall insulation.
Benefits of Cavity Wall Insulation
Save £150-£350/Year
Reduce heating bills by up to 35% annually
Warmer Home
Better heat retention in winter, cooler in summer
Add Property Value
Improve EPC rating and market appeal
Quick Installation
Completed in 2-4 hours with minimal disruption
Reduce Carbon Footprint
Cut CO2 emissions by 500-750kg per year
25-Year Guarantee
Long-lasting insulation with peace of mind
Get Your Cavity Wall Insulation Quote Today
Free eligibility check • Certified installers • Government grants available
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