Double-storey extensions in Portrush

Covering Portrush

Our coverage around Portrush (BT56) also includes Coleraine (4 miles to the south) and Ballymoney.

Homes in County Antrim

Housing in Northern Ireland mixes terraces in Belfast and Derry with detached houses and bungalows in towns and rural areas, many with room to extend.

What is a double-storey extension?

A double-storey extension adds new rooms on both the ground and first floor in one build, typically a larger kitchen or living space downstairs and an extra bedroom or bathroom above. Because the roof and foundations are shared, the cost per square metre is usually lower than a single-storey extension.

Planning and building control applications to the council
Measured survey, design and planning drawings
Windows, insulation, plastering, electrics and plumbing

How much should I budget for a double-storey extension?

Typical ranges for double-storey extensions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.

Double-storey extensions	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 £3,850 per m²

Do you need permission for a double-storey extension in Portrush?

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.

Two-storey extensions in Northern Ireland normally need planning permission from the council, plus building control approval.

What can change the price or programme?

Side extensions close to a boundary are often set back or stepped down so they do not create a terraced effect.
The first-floor link can mean moving a bathroom or reshaping the landing.

How does the project run?

Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
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 double-storey extension in Portrush

Is a two-storey extension better value than a single-storey one?

Per square metre, usually yes, because the foundations and roof serve two floors of space.

Will we need to move out?

Most people stay. The noisiest stage is when we break through into the existing first floor, which we plan for a short window.

How do I get a price for double-storey extensions in Portrush?

Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.

Also covering

Learn more about double-storey extensions, or see every project we cover in Portrush.