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 Ashton in Makerfield?
In Ashton in Makerfield, a garden annexe typically costs £1,700–£2,650 per m² of floor area, including VAT at 20% (standard rate). For a typical 35 m² project that is roughly £59,500–£93,000. Prices across the North West are typically 6% below the UK average for this kind of work, which is reflected in the range for Ashton in Makerfield. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (24 m²) | £41,000–£63,500 |
| Typical project (35 m²) | £59,500–£93,000 |
| Larger project (49 m²) | £83,500–£130,000 |
| Rate per m² | £1,700–£2,650 |
What moves the price most:
- Access for materials
- Kitchen and bathroom
- Drainage connection distance
- Cladding and finishes
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a garden annexe in Ashton in Makerfield?
Before anything is built in Ashton in Makerfield, we confirm which approvals apply in 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.
We check this for your address before design work starts, so there are no surprises later.
What we handle
From survey to sign-off, the job normally involves:
- Electrics and heating
- Kitchenette and shower room
- Insulated walls and roof
- External cladding or brickwork
- Planning drawings and application
- Glazed doors and windows
How long does it take?
Expect 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 Ashton in Makerfield
The North West has many brick terraces and inter-war semis, where kitchen extensions and dormer loft conversions add space without moving.
We work across Ashton in Makerfield and neighbouring areas such as Golborne, Newton-le-Willows and St Helens. Postcodes we cover in Ashton in Makerfield include WN4.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about garden annexes in Ashton in Makerfield
Can an annexe be rented out?
Not without further planning permission, as that would make it a separate dwelling.
How long does a garden annexe take in Ashton in Makerfield?
Typically 10 to 16 weeks on site. Design and approvals beforehand usually take 3 to 4 months.
Does a garden annexe need planning permission?
Usually yes if it is used as living accommodation. Outbuildings under permitted development must be incidental to the house, such as a gym or office, not bedrooms.
How much does a garden annexe cost in Ashton in Makerfield?
In Ashton in Makerfield, a garden annexe typically costs £1,700–£2,650 per m² of floor area, including VAT at 20% (standard rate). A typical 35 m² project comes to roughly £59,500–£93,000. Your fixed price depends on the survey and drawings.
Will council tax apply?
Annexes can be banded separately, though discounts or exemptions apply in some cases when occupied by family. Check with your council.