Covering Coulsdon
We work in Coulsdon (CR5) and the places around it, including Purley, Banstead and Sutton.
Homes in London
Much of London’s housing is Victorian and Edwardian terraces, which is why side return extensions, rear dormers and mansards are so common. Many streets are in conservation areas, and several boroughs use Article 4 directions that remove some permitted development rights.
What do you get with a garden annexe?
We design annexes as permanent buildings with proper foundations, insulation and services, and we prepare the planning case showing how the annexe will be used as part of the main home. Connections for water, drainage and power are planned from the start.
- Foundations and drainage connections
- Brick, block or timber-frame structure
- Kitchenette and shower room
How much does a garden annexe cost in Coulsdon?
Use these ranges to budget for garden annexes; the survey turns them into a fixed price for the agreed specification.
| 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 |
Do you need permission for a garden annexe in Coulsdon?
Projects in England go through two separate checks. Planning (or confirmation that the work is permitted development) comes from the district, borough or unitary council, and building regulations approval comes from the council’s building control team or a registered building control approver. Where work touches a shared wall or digs near a neighbour’s foundations, the Party Wall etc. Act 1996 applies.
A self-contained annexe used for sleeping and living normally needs planning permission in England.
What can affect a garden annexe?
- The annexe normally has to remain part of the main household, not let as a separate home.
- Drainage may need a pump if the garden falls away from the sewer.
What happens after I enquire?
- 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.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
Your questions answered
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 long does an annexe take to build?
About 14 to 24 weeks on site after approvals.
Do you work in Coulsdon?
Yes. Coulsdon is within our coverage for garden annexes, along with nearby Purley and Banstead.
Other towns nearby
- Garden annexes in Purley
- Garden annexes in Banstead
- Garden annexes in Sutton
- Garden annexes in Carshalton
Learn more about garden annexes, or see every project we cover in Coulsdon.

