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 Northamptonshire?
In Northamptonshire, a wraparound extension typically costs £2,100–£3,050 per m² of floor area, including VAT at 20% (standard rate). For a typical 28 m² project that is roughly £59,000–£85,500. Building costs in the East Midlands run about 5% below the UK average, and the figures for Northamptonshire are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (20 m²) | £42,000–£61,000 |
| Typical project (28 m²) | £59,000–£85,500 |
| Larger project (39 m²) | £82,000–£119,000 |
| Rate per m² | £2,100–£3,050 |
What moves the price most:
- Kitchen and flooring specification
- Access for materials on terraced streets
- Total footprint and the amount of glazing
- Drainage changes
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 Northamptonshire?
Here is how the rules work for a wraparound extension 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
The work we manage on a wraparound extension:
- Design and planning application
- Removal of internal and external walls
- Party wall notices and surveyor liaison
- Structural engineer’s design for steels and supports
- Walls, roof and glazing
- Foundations and drainage
How long does it take?
The build itself usually takes 12 to 18 weeks on site. Design and approvals come first and typically take 3 to 4 months, depending on the approval route.
Building in Northamptonshire
In the East Midlands, many estates built since the 1960s have integral garages that convert well into a study or bedroom.
Towns we cover in Northamptonshire include Northampton, Corby, Kettering, Wellingborough, Rushden and Daventry.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 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 Northamptonshire
How much does a wraparound extension cost in Northamptonshire?
In Northamptonshire, a wraparound extension typically costs £2,100–£3,050 per m² of floor area, including VAT at 20% (standard rate). A typical 28 m² project comes to roughly £59,000–£85,500. Your fixed price depends on the survey and drawings.
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.
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.
Who approves a wraparound extension in Northamptonshire?
Planning matters in Northamptonshire go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
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.