Cavity insulation for new builds and extensions for St Austell properties
St Austell sits in Cornwall, around 14 miles north-east of Truro. We work across the PL25 district, including nearby Bodmin, Truro and Newquay.
A suitable wall in St Austell is usually filled in a single day from outside, with drill holes made good to match the pointing. St Austell properties with rendered or painted walls get a closer look at the outer finish, because cracked render can let rain behind it.
Before any material is chosen, exposure is checked. Parts of Cornwall face some of the heaviest wind-driven rain in the UK, especially exposed coastal and upland sites. Here the survey is stricter: some walls suit only certain certified systems, and some should not be filled at all.
In terms of approvals, in St Austell 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 St Austell
- Clean-cavity working
- Trays, closers and stop ends as drawn
- Photo record for building control
- Coordination with your bricklayers
Guide prices for St Austell
| 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 St Austell property:
Tell us about the property
Postcode, property type and what you need.
Free survey
Walls, cavity, condition and exposure checked and photographed.
Written result and price
Suitable, suitable after repairs, or not suitable, with a fixed price.
Work and paperwork
Installation, making good, and the regulations and guarantee paperwork.