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 Edinburgh?
In Edinburgh, 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. Building costs in Scotland are close to the UK average, so the figures for Edinburgh are close to our national guide. 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 |
The biggest cost drivers are:
- Cladding and finishes
- Size and layout
- Drainage connection distance
- Kitchen and bathroom
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 Edinburgh?
Here is how the rules work for a garden annexe in Scotland. In Scotland an annexe with living accommodation needs planning permission and a building warrant.
In Scotland a building warrant is needed before work starts on most extensions, loft conversions and conversions. It is issued by the council’s building standards service. When the work is finished, a completion certificate is submitted and accepted by the council after inspection.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
Handled as part of most garden annexes:
- Building control sign-off
- Insulated walls and roof
- Foundations and drainage connections
- Glazed doors and windows
- External cladding or brickwork
- Kitchenette and shower room
How long does it take?
Allow 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 Edinburgh
Scotland’s housing ranges from sandstone tenements and villas to post-war and modern estates, and the building warrant system shapes how projects are planned.
We cover the whole of Edinburgh.
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
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 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 Edinburgh
Does it need building regulations?
Yes, as it contains sleeping accommodation and services.
Can it be accessible?
Yes. Level access, wider doors and a wet room can be designed in.
How long does a garden annexe take in Edinburgh?
Typically 10 to 16 weeks on site. Design and approvals beforehand usually take 3 to 4 months.
Do I need planning permission for a garden annexe in Edinburgh?
In Scotland an annexe with living accommodation needs planning permission and a building warrant.
How much does a garden annexe cost in Edinburgh?
In Edinburgh, 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.
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.
