Thinking about insulating your floors is a smart move if you want a warmer home and lower energy bills. But the first question is usually the most pressing: how much does floor insulation actually cost, and will the savings make it worthwhile?
For a typical UK semi-detached home, floor insulation costs range from £500 to £2,200 installed, with annual heating savings of up to £200. The exact figures depend on your floor type and whether you need to insulate a suspended timber floor or a solid concrete floor.
Floor insulation costs typically range from £500 to £2,200 depending on your home type
The cost of insulating your floor varies significantly based on the construction of your home. For a standard semi-detached house, insulating a suspended timber floor (the kind with a gap underneath) generally costs between £500 and £1,800. Solid concrete floors, which require a different approach, typically cost £800 to £2,200 (Energy Saving Trust, 2026).
These figures cover professional installation for a typical property. Larger homes, houses with complex layouts, or those with difficult access to the sub-floor will be at the higher end of the range. The final cost also depends on whether you choose DIY installation or hire a professional. DIY can cut costs significantly, but you must follow building regulations and ensure proper ventilation for timber floors.
The two main variables that determine your cost are the type of floor you have and how easy it is to access the space beneath it. Suspended timber floors are often simpler to insulate by lifting floorboards, while solid concrete floors may require a new layer of insulation on top, which can affect floor levels and skirting boards.
Annual savings on heating bills can reach up to £200 for an average semi-detached home
For a gas-heated semi-detached house with suspended timber floors, typical annual savings are between £50 and £200 per year. Solid concrete floor insulation saves roughly £40 to £150 annually, depending on how draughty your home was before installation (Energy Saving Trust, 2026).
Savings are lower for homes that already have modern insulation or are well-sealed. If your home already has decent underfloor insulation or minimal draughts, the additional benefit will be smaller. The biggest savings come from insulating a suspended timber floor that currently lets in cold air through gaps between floorboards or around the edges of the room.
These savings assume you have a gas boiler. If you use electric heating or a heat pump, your savings will be different because electricity costs more per unit of heat than gas. You can get a more accurate estimate by using the Energy Saving Trust’s home energy check tool.
Quick numbers cost, savings, and payback period
The table below gives a clear comparison of typical costs, annual savings, and payback periods for different floor insulation options. Payback period is the number of years it takes for the energy savings to cover the installation cost.
| Floor type | Typical cost (installed) | Annual savings | Simple payback period |
|---|---|---|---|
| Suspended timber floor (underfloor insulation) | £500 – £1,800 | £50 – £200 | 3 – 9 years |
| Suspended timber floor (draught-proofing only) | £100 – £300 | £20 – £60 | 2 – 5 years |
| Solid concrete floor (overlay insulation) | £800 – £2,200 | £40 – £150 | 5 – 15 years |
| Solid concrete floor (underfloor insulation) | £1,000 – £2,500 | £50 – £150 | 7 – 17 years |
Source: Energy Saving Trust, 2026
The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing.
The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. You may qualify if your home is in council tax bands A–E in England or A–F in Wales, and you receive certain benefits such as Pension Credit, Income Support, or Universal Credit (GOV.UK, 2026).
The scheme can cover up to 100% of the cost for eligible households. However, the installer you choose must be certified under the Microgeneration Certification Scheme (MCS). You cannot simply hire any local builder and claim the grant afterwards. The work must be approved and carried out by an MCS-certified company.
If you are not on benefits but your home has a low energy performance rating, you may still qualify under the “low-income” route if your property is in a low council tax band. Check your council tax band online before applying.
The Energy Company Obligation (ECO4) also funds floor insulation for low-income, fuel-poor homes
ECO4 is another government scheme that provides full or partial funding for floor insulation. It is targeted at households on means-tested benefits or those living in fuel poverty. To qualify, your property must have an Energy Performance Certificate (EPC) rating of D, E, F, or G (Ofgem, 2026).
The funding is delivered through your energy supplier, not directly from the government. You will need to contact your supplier to start the application process. The installer must be registered with TrustMark, which is a government-endorsed quality scheme that ensures consumer protection and high standards of workmanship.
ECO4 can cover the full cost of floor insulation for eligible households, but the amount depends on your supplier’s specific offer and the scope of work required. You may need to have a full assessment of your home’s energy efficiency before the work is approved.
You must use an MCS-certified installer to qualify for any government grant or scheme
The Microgeneration Certification Scheme (MCS) is the main standard for insulation installers under both GBIS and ECO4. Using an MCS-certified installer is not optional if you want grant funding. You can check the MCS installer database online to confirm your chosen company is certified before any work begins (MCS, 2026).
For ECO4-funded work, the installer must also be registered with TrustMark. TrustMark provides a complaints procedure and guarantees that the work meets industry standards. You can search the TrustMark database to find a registered tradesperson in your area (TrustMark, 2026).
If you are paying for the work yourself without any grant, you are not legally required to use an MCS-certified installer. However, using a certified professional gives you protection if something goes wrong and ensures the work meets building regulations.
Floor insulation is not usually eligible for the Boiler Upgrade Scheme (BUS)
The Boiler Upgrade Scheme (BUS) is designed to help with the cost of heat pumps and biomass boilers, not insulation measures like floor insulation (GOV.UK, 2026). You cannot claim BUS funding for floor insulation separately.
However, floor insulation can complement a heat pump installation. A heat pump works most efficiently when your home is well-insulated, because it runs at lower temperatures than a gas boiler. If you are planning to install a heat pump, consider adding floor insulation as a separate, unsubsidised improvement to maximise your heat pump’s performance and reduce your running costs.
The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing.
Boiler Upgrade Scheme costs and eligibility in 2026
You can check your eligibility online using your postcode and household details
The simplest way to find out what grants you qualify for is to use an online eligibility checker. The Energy Saving Trust’s home energy check tool asks for your postcode, property type, and heating system, then gives a tailored list of available funding (Energy Saving Trust, 2026).
The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. Both tools are free and take only a few minutes to complete.
These tools will tell you whether your property falls within the required council tax band and income bracket for GBIS or ECO4. They also flag any local authority grants that may be available in your area. Always check directly with your energy supplier as well, because they may have additional offers or waiting lists for ECO4 funding.
