Garden annexes · Barnes

Garden annexes in Barnes

Homeowners in Barnes can get garden annexes from one company: the design, the paperwork and the building work sit with us rather than with three separate firms.

Covering Barnes

Our coverage around Barnes (SW13) also includes Chiswick (1 miles to the north) and Putney.

Homes in London

Terraced houses dominate many London neighbourhoods, so most projects involve shared walls, narrow access and a party wall process. Conservation areas are widespread, and some boroughs have their own mansard and basement guidance.

What is included in a garden annexe in Barnes?

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
  • Heating, hot water and electrics

What will a garden annexe cost?

Use these ranges to budget for garden annexes; the survey turns them into a fixed price for the agreed specification.

Garden annexesGuide 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 Barnes?

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 affect a garden annexe?

  • Drainage may need a pump if the garden falls away from the sewer.
  • A level threshold and wider doors make the annexe suitable for later life.

From first call to completion

  1. Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
  2. Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
  3. Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
  4. Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.

Questions about a garden annexe in Barnes

How long does an annexe take to build?

About 14 to 24 weeks on site after approvals.

Can you make it wheelchair accessible?

Yes. Level access, wider doors and a level-access shower can be designed in from the start.

Can you visit a house in Barnes 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.

Garden annexes near Barnes

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

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