How much does external wall insulation cost in the UK?
A external wall insulation costs £90 to £160 in the UK, typically around £120 per m². Prices reviewed June 2026.
External wall insulation fixes insulation boards to the outside of the house and renders over them. It is priced by the wall area in square metres, and it is the main option for solid-wall homes with no cavity.
Price your external wall insulation
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External wall insulation cost breakdown
What a external wall insulation typically costs, by the unit:
| What | Typical UK cost |
|---|---|
| Per m², supplied and fitted | £90 to £160 per m² |
| + Brick-slip finish (not render) | add £30 to £70 per m² |
| Typical 90 m² | £8,100 to £14,400 |
What's included in the price?
A typical external wall insulation price includes:
- Scaffolding and preparation
- Insulation boards fixed to the walls
- A render or cladding finish
- Beads, trims and making good
What changes the price?
The things that move a external wall insulation price most:
Total wall area in square metres
Insulation thickness and the finish, render or brick-slip
Scaffolding and access
Detailing around windows, doors and the roofline
Does where you live change the cost?
London and the South East add 10 to 20 percent. Grants can cover part of the cost for eligible homes.
Common questions
At roughly £90 to £160 per square metre, a typical semi works out around £8,000 to £14,000, more for a larger or detached house. Grants can reduce this for eligible homes.
For a solid-wall home with no cavity it is one of the few ways to insulate the walls and can make a real difference to warmth and bills. It is a significant cost, so check for grants first.
These are independent guide prices based on typical UK jobs in 2026. Your actual cost depends on your property, spec, access and where you live. Always get at least three written quotes before committing.