The short answer
Removing cavity wall insulation in the UK typically costs from around £900 for a mid-terrace up to £3,500+ for a large detached property, with whole-house extraction often quoted in the region of £1,000–£4,000+ overall. A common per-square-metre figure is around £21.50/m², and a pre-extraction survey usually adds roughly £150–£400 depending on the detail and equipment used. Most whole-house jobs take one to three days. The main drivers are the wall area, the type of insulation (foam tends to be harder to clear than mineral fibre), the property height and whether scaffolding is needed, and how compacted or waterlogged the existing material is.
Price depends mainly on how much wall area there is, the type of insulation in the cavity and how accessible the walls are. The figures below are typical ranges for guidance, not quotations.
Typical UK costs
- Mid-terracefrom ~£900
- Semi-detached~£1,680
- Detached~£2,520
- Large detachedup to ~£3,500+
- Per square metre~£21.50/m²
- Survey~£150–£400
What drives the price
- Wall area: you pay largely by the area cleared, so a detached home with more external wall costs more than a mid-terrace.
- Insulation type: blown mineral fibre and bead clear differently from foam, and foam can be harder and slower to extract.
- Property height & access: a taller house, or awkward access, may need scaffolding, which adds to the figure.
- Condition of the fill: heavily compacted or waterlogged insulation takes longer to remove.
- Survey: a borescope survey before extraction typically adds £150–£400 and confirms what is in the cavity.
| Property | Typical extraction cost | Notes |
|---|---|---|
| Mid-terrace | from ~£900 | smallest wall area |
| Semi-detached | ~£1,680 | more external wall |
| Detached | ~£2,520 | more wall, often 2 storeys |
| Large detached | up to ~£3,500+ | largest area / access |
Indicative UK figures for guidance. Sources: Checkatrade and MyJobQuote cost guides.
Survey, access and the per-metre figure
Most reputable specialists start with a borescope survey to confirm the insulation type and condition before quoting extraction — that survey typically adds £150–£400. The extraction itself is often expressed as a per-square-metre rate, with a commonly quoted figure of around £21.50/m², though taller properties may need scaffolding which sits on top. Because the whole job usually takes one to three days, labour and access make up much of the cost, so a longer or higher elevation moves the number more than the material itself.
Frequently asked questions
How much does it cost to remove cavity wall insulation?
Typically from around £900 for a mid-terrace up to £3,500+ for a large detached property, with a common per-square-metre figure of about £21.50/m². A pre-extraction survey usually adds roughly £150–£400. The exact figure depends on wall area, insulation type and access.
Why is cavity wall insulation removal cost so variable?
Because properties differ. The external wall area, the type and condition of the insulation, the property height and whether scaffolding is needed all move the figure. A borescope survey gives the accurate number for your home.
Does removal include a survey?
Reputable specialists usually carry out a borescope survey first to confirm what is in the cavity, typically costing around £150–£400. Always check whether the survey, scaffolding and waste removal are included in the quoted price.
Sources & further reading
Figures on this page are typical UK ranges drawn from published sources and depend on your specific property. They are guidance, not a quotation.