Cavity insulation top-up for Portishead properties
We cover Portishead and the BS20 postcode district, including nearby Nailsea, Clevedon and Weston-super-Mare. It is about 35 miles north-east of Taunton.
Portishead properties with rendered or painted walls get a closer look at the outer finish, because cracked render can let rain behind it. Where a Portishead property has an extension or a conservatory, we check how the old and new walls meet, because that junction is often missed.
Before any material is chosen, exposure is checked. Somerset 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.
For regulations, in Portishead 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.
How do I know if my walls need a top-up?
Cold patches on internal walls, a thermal image showing uneven heat loss, or an EPC that says 'filled cavity' when parts of the house feel colder are all signs. Extensions are a common cause: the new wall is insulated as built, but the old wall it joins may have been left partly empty.
What is included in Portishead
- Written result with photos
- Borescope survey at several points
- Making good
- Map of filled and empty sections
Guide prices for Portishead
| Cavity insulation top-up guide prices | Guide price |
|---|---|
| Detached house | £1,295–£2,295 |
| Semi-detached house | £795–£1,495 |
| End-terrace house | £695–£1,295 |
| Detached bungalow | £695–£1,295 |
| Semi-detached bungalow | £595–£995 |
| Mid-terrace house | £595–£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 Portishead:
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.