Underfloor insulation across Wiltshire
We cover 4 towns in Wiltshire: Swindon, Salisbury, Trowbridge and Chippenham.
In Wiltshire homes this is often done on the same visit as a cavity fill, which saves a second trip. Small measures like this are often among the cheapest per pound saved, and they suit Wiltshire homes of every age.
Building Regulations in England
Filling an existing cavity wall is notifiable building work in England. Either a building notice goes to building control before the work, or the installer self-certifies it through a government-approved competent person scheme such as CIGA's CWISC scheme. The insulation used must also be suitable for the wall it goes into, which is why the survey checks construction, condition and exposure first.
Funding in England
- ECO4, the energy-supplier scheme, has been extended to 31 December 2026 and government has said there will be no successor supplier obligation.
- The Great British Insulation Scheme closed as planned on 31 March 2026.
- Warm Homes: Local Grant supports low-income households in England through councils, and the January 2026 Warm Homes Plan sets out fully funded upgrades for low-income homes, with more detail still being published.
Sources: Planning Portal: cavity wall insulation and building regulations; CIGA: CWISC competent person scheme; GOV.UK: extending the ECO4 end date, government response; GOV.UK: Warm Homes Plan.
Keeping the void ventilated
Air bricks under a suspended floor must stay clear so the timbers stay dry. Insulation goes between the joists, not across the void, and gaps at skirtings are sealed to stop draughts.
What is included
- Floor void inspection
- Insulation between joists
- Draught sealing at skirtings
- Boards relaid
Underfloor insulation prices in Wiltshire
| Underfloor insulation guide prices | Guide price |
|---|---|
| Suspended timber floor, typical room | £795–£1,495 |
| Whole ground floor | £1,995–£3,995 |
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.
From enquiry to finish in Wiltshire:
Get in touch
Online, by phone or WhatsApp.
Survey visit
We check the space, what is there now and how it is ventilated.
Your quote in writing
A fixed price, with any extras listed separately.
Booked work
Carried out by the installer named on your quote.