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 Heywood?
In Heywood, 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. That range is adjusted for the North West, where domestic building work typically costs around 6% below the national average. 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 |
The main things that change the cost:
- Size and layout
- Heating type
- 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 Heywood?
Here is how the rules work for a garden annexe 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
What we take care of:
- Kitchenette and shower room
- Glazed doors and windows
- Insulated walls and roof
- External cladding or brickwork
- Electrics and heating
- Building control sign-off
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 Heywood
The North West has many brick terraces and inter-war semis, where kitchen extensions and dormer loft conversions add space without moving.
Heywood sits in Greater Manchester, about 8 miles north of Manchester. We cover the whole of Heywood, including postcodes OL10.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 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 Heywood
Who approves a garden annexe in Heywood?
Planning matters in Heywood go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
How much does a garden annexe cost in Heywood?
In Heywood, 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.
Can it be accessible?
Yes. Level access, wider doors and a wet room can be designed in.
How long does it take?
Typically 10 to 16 weeks on site.
Can an annexe be rented out?
Not without further planning permission, as that would make it a separate dwelling.