What is a wraparound extension?
A wraparound extension combines a side return and a rear extension into one L-shaped addition. It gives the largest possible ground floor, often creating an open-plan kitchen, dining and living space across the whole width of the house.
How much does a wraparound extension cost in Horsham?
In Horsham, a wraparound extension typically costs £2,450–£3,600 per m² of floor area, including VAT at 20% (standard rate). For a typical 28 m² project that is roughly £68,500–£101,000. The guide for Horsham reflects typical costs in the South East, roughly 12% above the UK-wide figure. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (20 m²) | £49,000–£72,000 |
| Typical project (28 m²) | £68,500–£101,000 |
| Larger project (39 m²) | £95,500–£140,500 |
| Rate per m² | £2,450–£3,600 |
What moves the price most:
- Party wall surveyor fees for one or both neighbours
- Drainage changes
- Access for materials on terraced streets
- Kitchen and flooring specification
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for a wraparound extension in Horsham?
Before anything is built in Horsham, we confirm which approvals apply in England. In England a wraparound extension combines side and rear elements, which normally takes it outside permitted development, so a householder planning application is made.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
Handled as part of most wraparound extensions:
- Foundations and drainage
- Walls, roof and glazing
- Underfloor heating option, electrics and plastering
- Structural engineer’s design for steels and supports
- Design and planning application
- Party wall notices and surveyor liaison
How long does it take?
Build time is typically 12 to 18 weeks on site. Allow time beforehand for drawings and approvals, usually 3 to 4 months.
Building in Horsham
Commuter towns across the South East have many 1930s and post-war semis that suit rear extensions and hip-to-gable loft conversions.
If your home is in Horsham or close by in Crawley, Horley and Haywards Heath, a free home visit is the first step.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about wraparound extensions in Horsham
What about the old back addition?
The side wall of the back addition is usually removed and replaced with a steel beam, so the old kitchen joins the new space.
How much does a wraparound extension cost in Horsham?
In Horsham, a wraparound extension typically costs £2,450–£3,600 per m² of floor area, including VAT at 20% (standard rate). A typical 28 m² project comes to roughly £68,500–£101,000. Your fixed price depends on the survey and drawings.
Is a wraparound worth it?
It gives the biggest ground-floor space without going upwards. Whether it adds value depends on your street and house, so we suggest checking local sale prices before committing.
Who approves a wraparound extension in Horsham?
Planning matters in Horsham go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
Will both neighbours be affected?
Usually only the neighbour on the side return side, but rear foundations near either boundary can trigger party wall notices.