Covering Comber
We work in Comber (BT16, BT23) and the places around it, including Newtownards, Holywood and Belfast.
Homes in County Down
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?
Two-storey work has to sit comfortably with the house and the neighbours, so most of the design effort goes into the roofline, window positions and how the new first floor connects to the landing. We handle the planning application, the structural design and the building control process, then build, roof and finish both floors.
- Measured survey, design and planning drawings
- Foundations, steelwork, brick and block walls, roof
- Windows, insulation, plastering, electrics and plumbing
What is the guide price for a double-storey extension in Comber?
Use these ranges to budget for double-storey extensions; the survey turns them into a fixed price for the agreed specification.
| 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 |
Planning and building rules in Comber
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 should I think about before starting?
- Neighbours’ light is assessed using the 45-degree guide many councils use.
- The first-floor link can mean moving a bathroom or reshaping the landing.
What happens after I enquire?
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- 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.
Your questions answered
How much does a two-storey extension cost?
Typically about £2,400 to £3,850 per square metre of new floor area including VAT. A 40 m² extension across two floors is often around £100,000 to £150,000 depending on specification.
How long does a two-storey extension take?
Around 14 to 24 weeks on site, plus the planning period before that.
How do I get a price for double-storey extensions in Comber?
Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.
Double-storey extensions in nearby towns
- Double-storey extensions in Newtownards
- Double-storey extensions in Holywood
- Double-storey extensions in Belfast
- Double-storey extensions in Bangor
Learn more about double-storey extensions, or see every project we cover in Comber.

