Garden annexes in County Down

Covering County Down

We cover County Down, including Bangor, Newtownards, Newry and Banbridge, and the towns around them.

Homes in County Down

Across Northern Ireland you find city terraces, suburban semis and rural bungalows and farmhouses, so the right approach depends on the plot and the planning history.

What does a garden annexe involve?

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.

Foundations and drainage connections
Brick, block or timber-frame structure
Accessible design options for older relatives

What is the guide price for a garden annexe in County Down?

What garden annexes typically cost. These are guide ranges; the written quote for your house replaces them.

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

How is a garden annexe approved in County Down?

In Northern Ireland the council handles both planning and building control. Permitted development rules are set by the Planning (General Permitted Development) Order (Northern Ireland) 2015, and there is no party wall act, so we agree access and protection with neighbours in writing.

In Northern Ireland an annexe needs planning permission and building control approval.

What can affect a garden annexe?

The annexe normally has to remain part of the main household, not let as a separate home.
Drainage may need a pump if the garden falls away from the sewer.

What are the steps?

Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.

Questions about a garden annexe in County Down

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.

How much does a garden annexe cost?

Around £2,400 to £3,900 per square metre including VAT, depending on finish and services.

Who deals with the council for a project in County Down?

We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.

Also covering

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