Cavity insulation for new builds and extensions for Eastleigh properties
Our Hampshire coverage takes in Eastleigh (SO50) and nearby Southampton, Winchester and Totton. It is about 5 miles north-east of Southampton.
If a wall in Eastleigh 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. Eastleigh properties with rendered or painted walls get a closer look at the outer finish, because cracked render can let rain behind it.
Exposure matters for every cavity wall. Hampshire 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.
On compliance, in Eastleigh 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.
Extensions that join an older house
Where an extension meets an existing cavity wall, the junction is a weak point. We can borescope and fill the existing wall at the same time so the old and new walls perform together.
What is included in Eastleigh
- Trays, closers and stop ends as drawn
- Batts or boards to the specified U-value
- Photo record for building control
- Coordination with your bricklayers
Guide prices for Eastleigh
| 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.
How it works in Eastleigh:
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.