Garden annexes in Chiswick

Covering Chiswick

We work in Chiswick (W4) and the places around it, including Acton, Barnes and Shepherd's Bush.

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 does a garden annexe involve?

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.

Design and planning application
Kitchenette and shower room
Accessible design options for older relatives

How much should I budget for a garden annexe?

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

Planning and building rules in Chiswick

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 should Chiswick homeowners check first?

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.

How does the project run?

Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
Construction and completion. One site lead co-ordinates every trade through to the building control certificate.

Garden annexes: common questions

Can I rent the annexe out?

Usually not without a separate planning permission, because councils normally require it to stay part of the main house.

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 Chiswick?

Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.

Also covering

Learn more about garden annexes, or see every project we cover in Chiswick.