Floor Insulation
Insulate ground floors to cut heat loss and draughts. Funding may help eligible households with the cost
What is Floor Insulation?
Floor insulation adds a layer between your home and the cold ground. In suspended timber floors, common in homes built between the 1850s and 1950s, mineral wool or rigid boards are fitted between the joists. Solid concrete floors are usually insulated with rigid boards. Most homes only need to insulate the ground floor.
The Energy Saving Trust estimates floor insulation saves around £40-£100 a year depending on your home (around £55 for a semi, July 2026 prices), and it helps reduce draughts. In England the Warm Homes: Local Grant can include underfloor insulation, and ECO4 may help some households until 31 December 2026.
Key Benefits
Funding May Help
ECO4 (until 31 December 2026) or your council may fully or partly fund it for eligible homes
Lower Bills
Around £40-£100/year depending on home type (Energy Saving Trust)
Warmer Floors
Reduces draughts and makes rooms feel warmer
Access Matters
Easier from a cellar or crawl space; otherwise floorboards are lifted
Two Methods
Solid floor or suspended timber floor options
Keep Airbricks Clear
Ventilation under timber floors must be kept to stop damp and rot
Floor Insulation Costs
Funding May Help With the Cost
ECO4 ends on 31 December 2026 and work must be finished by then. It is not a grant: work may be fully or partly funded, and you may be asked to contribute. In England, councils also run the Warm Homes: Local Grant (EPC D-G, household income usually £36,000 or less). The Great British Insulation Scheme closed on 31 March 2026.
UK Energy Partnership is run by Harber Glaves Trading Ltd. We are not a government body and cannot decide who gets funding. Check eligibility with the official scheme: ECO4 or Warm Homes: Local Grant.
Typical costs, last reviewed September 2026. Source: Energy Saving Trust, July 2026 prices (unsubsidised, gas-heated home).
How Floor Insulation Works
Suspended Timber Floors
For homes with suspended timber floors, insulation boards or mineral wool are fitted between the floor joists from below (if accessible) or by lifting floorboards from above. These floors are typical in Victorian and Edwardian properties. The joists must be sound and free from damp or rot first.
Solid Concrete Floors
Existing solid floors are usually insulated by laying rigid insulation boards on top, then covering them with chipboard or other flooring. This raises the floor level, so door bottoms, skirting boards and sockets may need adjusting.
Installation Process
A surveyor assesses your floor type and recommends a method. How long it takes depends on the floor type, room sizes and access. The installer should keep underfloor ventilation such as airbricks clear to prevent damp and rot, and the work must meet building regulations.
Quick Grant Finder
Answer up to three quick questions to see which schemes may be worth checking
Ready for Floor Insulation?
Sending an enquiry is free. Better Home Hub, which runs this site, introduces installers who may be able to help. Check they are TrustMark registered before you agree to work.
Request Quotes from Installers