Covering Grantham
Grantham sits 22 miles south of Lincoln, with Newark-on-Trent 13 miles to the north-west and Melton Mowbray 14 miles to the south-west.
Homes in the East Midlands
Across the East Midlands you find everything from city terraces to modern estates and stone villages, so the right extension depends a lot on the street and the materials around it.
What goes into 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
- Kitchenette and shower room
- Accessible design options for older relatives
What will a garden annexe cost?
Typical ranges for garden annexes. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.
| 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 Grantham?
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. Permitted development for outbuildings does not cover living accommodation.
What should I think about before starting?
- A level threshold and wider doors make the annexe suitable for later life.
- Council tax treatment depends on who lives there; check with your council.
How does the project run?
- 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.
What people ask before starting
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 make it wheelchair accessible?
Yes. Level access, wider doors and a level-access shower can be designed in from the start.
How do I get a price for garden annexes in Grantham?
Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.
Garden annexes in nearby towns
- Garden annexes in Newark-on-Trent
- Garden annexes in Melton Mowbray
- Garden annexes in Oakham
- Garden annexes in West Bridgford
Learn more about garden annexes, or see every project we cover in Grantham.

