What is a garden annexe?

A garden annexe is a single-storey building in the garden with its own living space, bathroom and often a kitchenette, used by relatives, older children or guests. Unlike a garden room, it is built as habitable accommodation with foundations, insulation and services.
How much does a garden annexe cost in Wednesbury?
In Wednesbury, a garden annexe typically costs £1,750–£2,700 per m² of floor area, including VAT at 20% (standard rate). For a typical 35 m² project that is roughly £61,000–£94,500. Prices in the West Midlands sit near the national average for this kind of work, and the range for Wednesbury reflects that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (24 m²) | £42,000–£65,000 |
| Typical project (35 m²) | £61,000–£94,500 |
| Larger project (49 m²) | £86,000–£132,500 |
| Rate per m² | £1,750–£2,700 |
What moves the price most:
- Size and layout
- Heating type
- Cladding and finishes
- Access for materials
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for a garden annexe in Wednesbury?
Approvals for a garden annexe in Wednesbury follow the rules for England. In England an annexe used as living accommodation usually needs planning permission. Outbuildings built under permitted development must be incidental to the house, such as a gym or office, not a bedroom.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
What we take care of:
- Foundations and drainage connections
- Kitchenette and shower room
- Building control sign-off
- Electrics and heating
- Insulated walls and roof
- Glazed doors and windows
How long does it take?
The build itself usually takes 10 to 16 weeks on site. Design and approvals come first and typically take 3 to 4 months, depending on the approval route.
Building in Wednesbury
The West Midlands has large numbers of 1930s semis and Victorian terraces, which suit rear extensions, side extensions and dormer loft conversions.
From WS10 outwards, we take on projects throughout Wednesbury and the surrounding parts of the West Midlands.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about garden annexes in Wednesbury
Do you build garden annexes in Wednesbury?
Yes. We build garden annexes across Wednesbury, including postcodes WS10. Every project starts with a free home visit.
Can it be accessible?
Yes. Level access, wider doors and a wet room can be designed in.
Does it need building regulations?
Yes, as it contains sleeping accommodation and services.
Can an annexe be rented out?
Not without further planning permission, as that would make it a separate dwelling.
How much does a garden annexe cost in Wednesbury?
In Wednesbury, a garden annexe typically costs £1,750–£2,700 per m² of floor area, including VAT at 20% (standard rate). A typical 35 m² project comes to roughly £61,000–£94,500. Your fixed price depends on the survey and drawings.
