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 Mendip?
In Mendip, 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 Mendip 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 |
What moves the price most:
- Drainage changes
- Kitchen and flooring specification
- Steelwork and propping of the existing house
- Access for materials on terraced streets
Use the guide price tool to see how size and specification change the figure, then ask for a written, itemised quote.
Do you need planning permission for a wraparound extension in Mendip?
The approval route for Mendip 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.
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
From survey to sign-off, the job normally involves:
- Underfloor heating option, electrics and plastering
- Party wall notices and surveyor liaison
- Building control completion
- Removal of internal and external walls
- Design and planning application
- Foundations and drainage
How long does it take?
Expect 12 to 18 weeks on site. Before that, surveys, drawings and approvals usually take 3 to 4 months, longer if the council asks for changes.
Building in Mendip
The South West mixes stone and render cottages with post-war and newer estates, and local materials matter more here when matching an extension.
Projects in Mendip (BA5) are surveyed in person before we quote, so the price reflects your actual property.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about wraparound extensions in Mendip
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.
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.
How much does a wraparound extension cost in Mendip?
In Mendip, 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.
How long does a wraparound extension take in Mendip?
Typically 12 to 18 weeks on site. Design and approvals beforehand usually take 3 to 4 months.
Can we keep a separate living room?
Yes. Many clients keep the front room separate and open up only the back of the house.
