Loft insulation prices
Guide prices for every loft job we do. Your fixed price follows a free survey for installation work. Prices include VAT where it applies; installing insulation in a home is zero-rated until 31 March 2027.
How much does it cost to insulate a loft from bare joists?
| Home, average loft | Essential 270 mm mineral wool and lagging | Recommended 300 mm, hatch and lagging | Natural fibre Sheep's wool, hatch and lagging |
|---|---|---|---|
| Top-floor flat | £495 to £845 | £795 to £1,295 | £1,345 to £2,095 |
| Terraced house | £495 to £745 | £745 to £1,195 | £1,195 to £1,895 |
| Semi-detached or end-terrace | £545 to £945 | £845 to £1,395 | £1,495 to £2,295 |
| Detached house | £745 to £1,245 | £1,095 to £1,745 | £1,895 to £2,945 |
| Bungalow | £895 to £1,445 | £1,245 to £1,945 | £2,195 to £3,345 |
The Energy Saving Trust puts a typical professionally installed loft at about £750 from bare joists in Great Britain, and about £1,100 in Northern Ireland.
How much does a top-up cost?
| Home, average loft | From about 100 mm | From 150 to 200 mm |
|---|---|---|
| Top-floor flat | £395 to £595 | £395 to £495 |
| Terraced house | £395 to £545 | £395 to £495 |
| Semi-detached or end-terrace | £395 to £645 | £395 to £495 |
| Detached house | £495 to £845 | £395 to £695 |
| Bungalow | £595 to £995 | £445 to £795 |
What do the other loft jobs cost?
| Service | Guide price | Based on |
|---|---|---|
| Loft insulation top-up | £395 to £545 | Terraced house, average loft, topping up from about 100 mm |
| Blown loft insulation | £595 to £795 | Terraced house, average loft |
| Natural loft insulation | £995 to £1,495 | Terraced house, average loft, sheep's wool |
| Rafter insulation | £1,645 to £2,595 | About 30 m² of roof slope |
| Room-in-roof insulation | £3,995 to £8,995 | One room-in-roof, depending on size and finish |
| Loft boarding | £695 to £895 | A raised storage area of about 10 m² |
| Insulated loft hatches | £245 to £395 | Insulated hatch in the existing opening |
| Loft ladder fitting | £295 to £545 | Ladder into a suitable existing hatch |
| Loft insulation removal | £445 to £645 | Terraced house, average loft, removal only |
| Spray foam removal | £1,495 to £1,995 | Terraced house, open-cell foam, removal only |
| Loft ventilation | £245 to £695 | Eaves or tile vents for a typical house |
| Loft condensation investigation | £145 to £245 | Investigation visit with written findings |
| Pipe and tank lagging | £95 to £195 | Tank jacket and pipe lagging, typical loft |
| Loft insulation survey | £95 to £165 | Standalone survey with a written report |
| Thermal imaging survey | £165 to £295 | Survey and report for a typical house |
| Loft insulation grants check | No charge | Funding check |
| Period home loft insulation | £995 to £1,495 | Terraced house, average loft, natural fibre; mineral wool, where it suits, costs less |
| Loft insulation for flats | £495 to £845 | One top-floor flat, from bare joists |
| Landlord loft insulation | £495 to £745 | Per terraced house, from bare joists |
| Commercial roof void insulation | £9 to £18 per m², before any VAT | Per m² of roof void, before any VAT; access equipment extra |
| New-build loft insulation | £5 to £9 per m², before any VAT | Per m², supply and fit, before any VAT |
What changes the price?
- The loft floor area, which follows the footprint of the house
- What is there now, and whether it can stay
- Access, pitch and how much is stored in the loft
- Extras such as raised boarding, a hatch, a ladder or ventilation
- The material chosen
Installing insulation in a home is zero-rated for VAT until 31 March 2027 and 5% after that, under HMRC's rules for energy-saving materials (notice 708/6). Boarding, ladders, ventilation, surveys and investigations are not energy-saving materials, so they are standard-rated if VAT applies. Where they are done alongside insulation, the quote shows each part separately. Commercial and trade prices are shown before any VAT.
