Removal and re-insulation, quoted as one job
Once spray foam comes out, the loft has no insulation left at all, so re-insulation is not an optional extra, it is part of finishing the job properly. We quote removal and re-insulation together as one fixed price, so you are not left with a second bill and a second visit.
Why it matters
Why quoting these separately costs you more
A quote for removal alone leaves out the fact that the roof is bare once the foam is gone. Getting a second company in for re-insulation means a second site visit, sometimes a second access charge, and weeks or months with an uninsulated roof in between, which shows up directly in a winter heating bill. It also creates the exact condensation risk the original inspection was trying to catch in the first place, on a roof that has just had its old insulation stripped out and nothing put back.
There is a quieter risk too. Once the drama of removal is over and the invoice is paid, re-insulation is easy to put off. A job quoted and booked as one piece of work does not have that gap to fall into.
The standard
What current Building Regulations require
Once the foam is out, the replacement insulation has to meet the same standard as any other loft refurbishment. Approved Document L, Volume 1, for existing dwellings, the 2021 edition that has applied in England since June 2022, sets the target: a cold loft insulated at ceiling or joist level needs to reach a U-value of 0.16 W/m²K, which in practice means around 270mm of standard mineral wool quilt, or slightly less with a higher-performance product. A room-in-roof, where insulation sits at rafter level instead of on the loft floor, has a marginally less demanding target of 0.18 W/m²K, usually met with around 100mm to 120mm of rigid PIR board fitted between and under the rafters, because there is far less depth available to work with.
Source: Approved Document L, Volume 1, conservation of fuel and power for existing dwellings, 2021 edition, effective in England since June 2022, read September 2026. Scotland and Wales apply their own versions of the same principle, with broadly similar targets; ask your installer to confirm the figure that applies where you live before work starts.
The options
Which insulation goes back, and where
The right option depends on the roof and how you use the loft, not on price alone. This is quoted properly at survey, once we know which one fits.
| Option | Where it goes | Typical depth | Best for |
|---|---|---|---|
| Mineral wool at joist level | Laid between and over the ceiling joists, at the loft floor | Around 270mm | A loft you do not use as a room, where the floor can simply be reboarded over the top |
| Rigid PIR board between rafters | Fixed between and under the rafters, following the line of the roof | Around 100mm to 120mm | A room-in-roof conversion, or a loft used as habitable space where floor-level insulation is not an option |
| Warm roof, insulation above the rafters | A continuous layer above the rafters, under a new external roof covering | Varies by product | Where the roof covering itself is being renewed at the same time, not a like-for-like re-insulation on its own |
Cost
What re-insulation adds, by property size
Re-insulation runs £10 to £37 per square metre on top of the removal cost, priced against the treated roof area rather than the floor area, because that is the area losing heat once the foam is gone.
| Property | Treated roof area | Re-insulation |
|---|---|---|
| Terraced house | 35 to 55m² | £1,800 to £2,050 |
| Semi-detached house | 55 to 80m² | £1,800 to £2,950 |
| Bungalow | 60 to 95m² | £1,800 to £3,500 |
| Detached house | 80 to 120m² | £1,800 to £4,450 |
| Large detached or barn conversion | 120 to 200m² | £1,800 to £7,400 |
Figures are for standard mineral wool or PIR at the depths above. Warm roof re-insulation is priced separately once the roof covering scope is known.
No obligation, no deposit
Have someone look at it properly
An hour in the loft and you will know exactly where you stand, in writing, with photographs. If the foam is sound, that is what the report says and there is nothing to pay.
Book the free inspection
Two steps. No deposit, and nothing to pay if the foam is sound.
What happens if you only get removal quoted
The roof stays exposed until someone else is booked, which on a live sale or a remortgage is usually the worst possible moment to have an uninsulated loft and no fixed date for the follow-up job. It also weakens the evidence pack: a completion certificate that only covers removal, without a re-insulation specification, is a smaller and less convincing document than one that shows the roof was put right and left compliant. See what a full evidence pack should actually contain.
Our rules, published
What we will never do
Trading Standards has prosecuted spray foam operations in this market, including a 2024 case with 25 victims whose average age was 77. Pretending that is not happening helps nobody. These are our rules and every one of them is checkable.
- We never cold call. If someone rang you unprompted about your loft, it was not us.Trading Standards has prosecuted cold-call spray foam operations, including a 2024 case with 25 victims whose average age was 77.
- We never take a deposit. You pay when the work is done and inspected.Advice Direct Scotland has warned about deposit-taking removal firms; one reported case took £550 against a £5,500 quote.
- We will tell you if the foam can stay.The Insulation Manufacturers Association stated in February 2026 that correctly installed foam is safe and rarely needs removing.
- We never claim your home is on a national database or worthless.The Property Care Association named that claim as fabricated in August 2026. No such database exists.
- The price is written down before anything starts.It changes only if you ask for extra work, in writing.
- If the membrane is damaged, the report says so.Foam frequently bonds to and destroys the old felt. Covering that up is the failure the PCA's new removal standard is written to stop.
Removal and re-insulation questions
Do I have to re-insulate the loft after spray foam removal?
Yes, in practice. Once the foam is out the roof has no insulation at all, and leaving it that way costs you in heating bills immediately and leaves the loft outside current Building Regulations. It is quoted and carried out as part of the same job.
What insulation goes back in after spray foam comes out?
Mineral wool at joist level for a loft that stays a loft, or rigid PIR board between the rafters for a room-in-roof. Which one fits depends on how you use the space, confirmed at survey.
Does re-insulation meet Building Regulations automatically?
Only if it is installed to the current specification: around 270mm of mineral wool at ceiling level, or a U-value of 0.18 W/m²K at rafter level, per Approved Document L. Ask for the specification in writing as part of your evidence pack, not just a description of the material used.
How much does re-insulation cost on its own?
£10 to £37 per square metre of treated roof area. On a standard three-bed semi that is typically £1,800 to £2,950, on top of the removal and disposal cost.
Can I turn the loft into a room while I am having this done?
If you choose rafter-level insulation as part of a wider room-in-roof conversion, that becomes a bigger project with its own building control requirements beyond insulation alone, including structural and fire considerations. We quote the insulation correctly either way; a full conversion is a separate conversation.
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