Covering Northampton
Alongside Northampton, we also cover Wellingborough (9 miles to the north-east), Towcester and Daventry.
Homes in the East Midlands
The East Midlands combines red-brick terraces in the cities with a lot of post-war and modern estate housing, so rear extensions, garage conversions and loft conversions are all common.
What does a garden annexe involve?
A garden annexe is a separate single-storey building in the grounds of a house with its own bedroom, bathroom and kitchenette, used by family members as part of the main household. Unlike a garden office, an annexe that people sleep in normally needs planning permission and full building regulations approval.
- Design and planning application
- Foundations and drainage connections
- Brick, block or timber-frame structure
What is the guide price for a garden annexe in Northampton?
What garden annexes typically cost. These are guide ranges; the written quote for your house replaces them.
| Garden annexes | Guide price incl. VAT |
|---|---|
| Standard specification | £2,400 to £2,900 per m² |
| Good specification | £2,900 to £3,400 per m² |
| High specification | £3,400 to £3,900 per m² |
How is a garden annexe approved in Northampton?
In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it applies.
A self-contained annexe used for sleeping and living normally needs planning permission in England. Permitted development for outbuildings does not cover living accommodation.
What can change the price or programme?
- Drainage may need a pump if the garden falls away from the sewer.
- Council tax treatment depends on who lives there; check with your council.
What are the steps?
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
- Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
Questions about a garden annexe in Northampton
Do I need planning permission for a garden annexe?
Usually yes, because people will sleep in it. Outbuilding permitted development does not cover living accommodation.
How much does a garden annexe cost?
Around £2,400 to £3,900 per square metre including VAT, depending on finish and services.
Can you visit a house in Northampton to quote?
Yes. After a short call we arrange a site visit to measure up and agree what the design needs to do, then send a written price.
Other towns nearby
- Garden annexes in Wellingborough
- Garden annexes in Towcester
- Garden annexes in Daventry
- Garden annexes in Rushden
Learn more about garden annexes, or see every project we cover in Northampton.

