Party wall cavity insulation for Hanworth properties
Hanworth sits in Greater London, around 12 miles south-west of London. We work across the TW13 district, including nearby Hampton, Feltham and Hounslow.
Most Hanworth 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. If a wall in Hanworth 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.
Local weather affects which walls can be filled. Much of Greater London sits in the more sheltered driving-rain zones of the UK, which widens the choice of fill. Exposed elevations, coastal sites and high ground still get checked wall by wall.
For regulations, in Hanworth 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 need from you and your neighbour
The cavity is shared, so we talk you through notifying your neighbour before work. Filling is done from your side, usually through the loft. The survey confirms the wall is a cavity wall and not solid masonry, and checks for cables, flues and any gaps that would let fill escape.
What is included in Hanworth
- Loft inspection and borescope check
- Neighbour notification guidance
- Certified fill to the separating wall
- Sealing at the top of the cavity
Guide prices for Hanworth
| Party wall cavity insulation guide prices | Guide price |
|---|---|
| Party wall, two-storey house | £595–£895 |
| Party wall, bungalow | £395–£695 |
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.
What happens next for a Hanworth 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.