Typical 2026 UK costs by house type and per m², the savings you could make, and how to get a fair price.
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Loft insulation is one of the best value ways to warm a home, and one of the cheapest to install. Insulating an uninsulated loft to the recommended 270mm typically costs around £650 to £1,200 depending on your house size, and a basic quilt job averages about £725. Here is the full breakdown by house type and per m², what you could save, and how to pay a fair price.
These are typical figures for an uninsulated loft taken to 270mm. A detached house can save around £360 a year on energy bills, the most of any property type.
| House type | Typical installation cost | Typical annual bill saving |
|---|---|---|
| Detached house | £1,206 | £360 |
| Semi-detached house | £825 | £190 |
| Mid-terrace house | £654 | £140 |
| Detached bungalow | £1,206 | £350 |
Sources: annual savings from the Energy Saving Trust (England, Scotland & Wales); installation costs from Checkatrade (July 2026). Verified August 2026. Typical estimates only, your quote will vary.
Priced by area and material, here is a rough guide (materials only, so add labour):
| Material | Typical cost per m² (materials) |
|---|---|
| Quilt / mineral wool roll | Around £10 |
| Loose-fill (blown) | Around £12 |
| Thermal foil layer | Around £14 |
| PIR board | Around £35 |
Per-m² figures: Checkatrade, July 2026, materials only. Most lofts are quoted per job rather than per m².
Around a quarter of a home's heat escapes through an uninsulated roof, so insulating it makes a real difference. On Energy Saving Trust figures the yearly saving ranges from about £140 for a mid-terrace up to around £360 for a detached house. Because loft insulation lasts around 40 years, it pays for itself many times over across its life, which is why it is usually the first improvement worth making.
The main factors are the size of your loft in square metres, the material and depth, how easy the space is to access, and whether you are starting from scratch or topping up. Insulating at rafter level to create a warm loft costs more than a standard loft-floor job, and a boarded loft for storage adds to the price too.
For most homes, clearly yes. It is low cost, quick, long lasting and cuts a big share of heat loss. If your loft is dry and easy to access you may even be able to insulate it yourself, though for damp, awkward or rafter-level work it is best to use a professional.
Eligible households may get loft insulation funded through a grant, so check our 2026 insulation grants guide. Either way, comparing quotes is the best way to keep costs down. See our insulation cost overview and cavity wall insulation cost guide, and read our full loft insulation guide and the right loft insulation depth before you get quotes.
Insulating an uninsulated loft to the recommended 270mm typically costs around £650 to £1,200 depending on your house size, and a basic quilt job averages about £725. Topping up existing insulation from 120mm to 270mm is cheaper, around £600. Costs vary, so compare quotes.
By material and area, expect roughly £10 per m² for quilt (mineral wool) rolls, about £12 for loose-fill and £14 for a thermal foil layer, rising to around £35 per m² for PIR board, based on Checkatrade materials-only figures for July 2026. Labour is on top, and most lofts are quoted per job rather than per m².
Insulating a completely uninsulated loft can save around £360 a year for a detached house, £350 for a bungalow, £190 for a semi-detached and £140 for a mid-terrace, according to the Energy Saving Trust. Around a quarter of a home's heat escapes through an uninsulated roof, so the comfort gain is significant too.
For most homes, yes. Loft insulation is one of the cheapest high-impact improvements you can make, it lasts around 40 years, and it cuts a large share of your heat loss. It is usually the first place to start before more expensive measures.
Possibly. Eligible low-income households may get loft insulation funded through ECO4 or the Warm Homes: Local Grant. See our 2026 insulation grants guide and confirm current eligibility.
If your loft is easy to access, dry and not a flat roof, DIY with mineral wool rolls can cost less than professional installation. If there is any damp, awkward access or you want it insulated at rafter level, use a professional. Either way, get the depth and ventilation right.
Tell us about your home and we will match you with vetted installers so you can compare no cost quotes and see a fair price.
Insulation Advice Centre