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 Northampton?
In Northampton, 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 Northampton 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:
- Total footprint and the amount of glazing
- Party wall surveyor fees for one or both neighbours
- Drainage changes
- Kitchen and flooring specification
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for a wraparound extension in Northampton?
Approvals for a wraparound extension in Northampton follow the rules for 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.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
On a typical wraparound extension we handle:
- Structural engineer’s design for steels and supports
- Removal of internal and external walls
- Walls, roof and glazing
- Building control completion
- Underfloor heating option, electrics and plastering
- Design and planning application
How long does it take?
Expect 12 to 18 weeks on site. Allow time beforehand for drawings and approvals, usually 3 to 4 months.
Building in Northampton
In the East Midlands, many estates built since the 1960s have integral garages that convert well into a study or bedroom.
Projects in Northampton (NN1) are surveyed in person before we quote, so the price reflects your actual property.
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 handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about wraparound extensions in Northampton
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.
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 Northampton?
In Northampton, 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.
How long does it take to build?
Around 12 to 18 weeks on site after approvals. Design, planning and party wall matters usually take 3 to 4 months beforehand.
Do you build wraparound extensions in Northampton?
Yes. We build wraparound extensions across Northampton, including postcodes NN1. Every project starts with a free home visit.