Garden annexes in Hanworth

Covering Hanworth

Hanworth sits 12 miles south-west of London, with Feltham 2 miles to the north-west and Sunbury-on-Thames 3 miles to the south-west.

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 Hanworth?

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.

Brick, block or timber-frame structure
Heating, hot water and electrics
Accessible design options for older relatives

What is the guide price for a garden annexe in Hanworth?

Indicative costs for garden annexes. London and the South East usually sit towards the top of each range.

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 Hanworth?

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.

What can affect a garden annexe?

The annexe normally has to remain part of the main household, not let as a separate home.
Council tax treatment depends on who lives there; check with your council.

From first call to completion

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.
Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.

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.

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.

How do I get a price for garden annexes in Hanworth?

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

Other towns nearby

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