Party wall cavity insulation for Durham properties
We cover Durham and the DH1 postcode district, including nearby Chester-le-Street, Stanley and Bishop Auckland. Durham is one of the main towns we cover in County Durham.
If a wall in Durham is not suitable, for example because of an undiagnosed damp patch or a very exposed gable, you are told so in writing with the reason. A suitable wall in Durham is usually filled in a single day from outside, with drill holes made good to match the pointing.
Wind-driven rain is the first thing the surveyor weighs up. 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.
In terms of approvals, 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 need from you and your neighbour
The cavity is shared, so we talk you through notifying your neighbour before work. Filling is done from your side, usually through the loft. The survey confirms the wall is a cavity wall and not solid masonry, and checks for cables, flues and any gaps that would let fill escape.
What is included in Durham
- Neighbour notification guidance
- Certified fill to the separating wall
- Loft inspection and borescope check
- Sealing at the top of the cavity
Guide prices for Durham
| Party wall cavity insulation guide prices | Guide price |
|---|---|
| Party wall, two-storey house | £595–£895 |
| Party wall, bungalow | £395–£695 |
No VAT is charged on installing insulation in homes until 31 March 2027 (then 5%). 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:
Get in touch
Online, by phone or WhatsApp, whichever suits you.
Survey visit
The surveyor checks each wall and looks into the cavity where needed.
Your result in writing
What we found, what it means, and a fixed price if work is needed.
Booked work
Carried out by the installer named on your quote, with their scheme registrations.