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 Wiltshire?
In Wiltshire, a wraparound extension typically costs £2,250–£3,250 per m² of floor area, including VAT at 20% (standard rate). For a typical 28 m² project that is roughly £63,000–£91,000. Building costs in the South West are close to the UK average, so the figures for Wiltshire are close to our national guide. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (20 m²) | £45,000–£65,000 |
| Typical project (28 m²) | £63,000–£91,000 |
| Larger project (39 m²) | £88,000–£127,000 |
| Rate per m² | £2,250–£3,250 |
Your quote will depend mainly on:
- Total footprint and the amount of glazing
- Drainage changes
- Kitchen and flooring specification
- Steelwork and propping of the existing house
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a wraparound extension in Wiltshire?
The approval route for Wiltshire is set by planning law 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.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
On a typical wraparound extension we handle:
- Design and planning application
- Removal of internal and external walls
- Underfloor heating option, electrics and plastering
- Party wall notices and surveyor liaison
- Foundations and drainage
- Structural engineer’s design for steels and supports
How long does it take?
The build itself usually takes 12 to 18 weeks on site. Allow time beforehand for drawings and approvals, usually 3 to 4 months.
Building in Wiltshire
The South West mixes stone and render cottages with post-war and newer estates, and local materials matter more here when matching an extension.
Towns we cover in Wiltshire include Swindon, Salisbury, Trowbridge, Chippenham and Melksham.
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
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about wraparound extensions in Wiltshire
How long does a wraparound extension take in Wiltshire?
Typically 12 to 18 weeks on site. Design and approvals beforehand usually take 3 to 4 months.
How much does a wraparound extension cost in Wiltshire?
In Wiltshire, a wraparound extension typically costs £2,250–£3,250 per m² of floor area, including VAT at 20% (standard rate). A typical 28 m² project comes to roughly £63,000–£91,000. 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.
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.
Can we keep a separate living room?
Yes. Many clients keep the front room separate and open up only the back of the house.
