Cavity insulation for new builds and extensions for Havant properties
We cover Havant and the PO9 postcode district, including nearby Waterlooville, Portsmouth and Gosport. It is roughly 19 miles east of Southampton.
A suitable wall in Havant is usually filled in a single day from outside, with drill holes made good to match the pointing. Most Havant houses built from the 1920s onwards have cavity walls, but the survey still checks each one: cavity width, debris, the condition of the brickwork and how exposed each wall is.
Wind-driven rain is the first thing the surveyor weighs up. 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.
As for paperwork, in Havant 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 Havant
- Trays, closers and stop ends as drawn
- Photo record for building control
- Batts or boards to the specified U-value
- Clean-cavity working
Guide prices for Havant
| 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 Havant:
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.