Cavity insulation top-up for Horsham properties
Our West Sussex coverage takes in Horsham (RH12) and nearby Crawley, Haywards Heath and Burgess Hill. It is about 7 miles south-west of Crawley.
Where a Horsham property has an extension or a conservatory, we check how the old and new walls meet, because that junction is often missed. If a wall in Horsham 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.
Wind-driven rain is the first thing the surveyor weighs up. West Sussex 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.
On compliance, in Horsham 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.
When a top-up is not enough
If the existing fill is wet, contaminated with debris or breaking down, adding more on top can make things worse. In that case we tell you the honest option, which may be partial or full removal and refill.
What is included in Horsham
- Borescope survey at several points
- Making good
- Targeted fill with a compatible system
- Written result with photos
Guide prices for Horsham
| 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 Horsham:
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.