Cavity insulation for new builds and extensions for Durham properties
Durham is among the towns we cover in County Durham, alongside Chester-le-Street, Stanley and Bishop Auckland. Durham is one of the main towns we cover in County Durham.
For semi-detached and terraced homes in Durham, cavity barriers are fitted where your wall meets your neighbour's so the fill stays on your side. Where a Durham property has an extension or a conservatory, we check how the old and new walls meet, because that junction is often missed.
Before any material is chosen, exposure is checked. County Durham has a mix of moderate and more exposed sites. Hilltop, coastal and west-facing walls take the brunt of wind-driven rain, so the survey records exposure for each elevation before a material is chosen.
For regulations, in Durham filling a cavity is notifiable building work and needs a building notice or competent-person self-certification.
Funding in England
In England, ECO4 runs to 31 December 2026 and Warm Homes: Local Grant supports low-income households through councils.
Sources: GOV.UK: extending the ECO4 end date, government response; GOV.UK: Warm Homes Plan.
What we work from
Your architect's or designer's specification and the energy calculation for the job. We match the product, thickness and fixing to that spec, keep cavities clean as the walls rise, and fit cavity trays, closers and stop ends where shown so the building control inspection goes smoothly.
What is included in Durham
- Coordination with your bricklayers
- Trays, closers and stop ends as drawn
- Batts or boards to the specified U-value
- Photo record for building control
Guide prices for Durham
| Cavity insulation for new builds and extensions guide prices | Guide price |
|---|---|
| Full-fill batts supplied and fitted, per m² | £9–£16 |
| Partial-fill boards supplied and fitted, per m² | £14–£26 |
Prices are shown before any VAT; the VAT treatment for new-build work is confirmed on your quote. Guide ranges only: the fixed price is confirmed in writing before any work starts, and anything that could not be seen at survey is agreed with you first.
What happens next for a Durham property:
Send your details
A minute online, or call the free number.
We check the walls
Construction, cavity width, debris, damp and wind-driven rain exposure.
You decide
Plain-English result and a fixed price, with no pressure to book.
Job done properly
Holes made good, paperwork handed over, guarantee details confirmed.