Two-storey side extensions in Bangor (County Down)
Our two-storey side extensions service in Bangor (County Down) covers everything: measured survey, design, planning or permitted development checks, structural design, building control and the build itself.
The basics for Bangor (County Down) at a glance.
- Postcode districts
- BT19 and BT20
- County / area
- County Down, Northern Ireland
- Price region
- Northern Ireland
- Guide price
- £76,000–£101,500 (£1,800–£2,420 per m²)
- Approval route
- Planning permission is needed: permitted development side extensions in Northern Ireland can't be more than 4 m high, which rules out two storeys.
- Nearest towns
- Newtownards (4.8 miles), Donaghadee (5.5 miles), Holywood (6.4 miles)
- First visit
- Free, no obligation
About a two-storey side extension
A two-storey side extension is a new two-floor addition built into the space beside your house, often over a driveway or side passage. It typically adds one or two bedrooms upstairs and a utility, study or larger kitchen below, without giving up rear garden.
We cover postcode districts BT19 and BT20 in and around Bangor (County Down), along with neighbouring Newtownards, Donaghadee and Holywood.
What it costs in Bangor (County Down)
Guide prices for two-storey side extensions in Northern Ireland are around £1,800–£2,420 per m² of new floor space, including VAT. For a typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space), that's roughly £76,000–£101,500. Steelwork for wide openings is the item most likely to move the figure; we'll know once the engineer has designed it.
| Spec | Per m² | A 3 m × 7 m footprint on two floors (42 m² of new floor space) |
|---|---|---|
| Essential | £1,660–£2,230 per m² | £69,500–£93,500 |
| Standard | £1,800–£2,420 per m² | £76,000–£101,500 |
| Premium | £2,160–£2,900 per m² | £91,000–£122,000 |
Planning and building control in Bangor (County Down)
In Northern Ireland, permitted development for two-storey work is set out for rear extensions, so a two-storey side extension normally needs a planning application. The fee is £347 per dwelling, and councils aim for an average of 15 weeks on local applications. You also need building control approval from the council under the Technical Booklets.
Approval in Northern Ireland: Planning application for works to a house: £347. Councils aim to decide local applications within an average of 15 weeks; many take longer.
Building control: Building control approval from the local council under the Building Regulations (Northern Ireland), using the Technical Booklets.
Design points for Bangor (County Down) homes
Avoiding a terracing effect
Where semi-detached houses sit close together, side extensions on neighbouring houses can join up and turn a row of pairs into a terrace. Many councils ask for a gap to the boundary at first floor to stop this, so we check local guidance before fixing the width.
Access and services
Side extensions often cover the only route to the back garden, a gas meter, soil pipes or a drain run. We plan bin and bike access, move meters and pipes where needed and check drains early, because these items affect both cost and layout.
How we'd run your project
Visit and first ideas
One of our team visits your house in Bangor (County Down), checks the walls, roof and drains, and sketches out options with you.
Choose the approval route
Some designs fit permitted development, most need a householder application. We decide which applies in Northern Ireland before drawing in detail.
Engineer it
Foundations sized for two floors, steels for any openings, and building control approval, all before anyone starts on site.
Finish and certify
Second fix, plastering and making good, then building control's final inspection and the completion paperwork.
Questions about two-storey side extensions in Bangor (County Down)
Who handles building control for a project in Bangor (County Down)?
We handle it as part of the project. What's needed in Northern Ireland: building control approval from the local council under the Building Regulations (Northern Ireland), using the Technical Booklets. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.
Do I need planning permission for a two-storey side extension in Bangor (County Down)?
Bangor (County Down) is in Northern Ireland. Planning permission is needed: permitted development side extensions in Northern Ireland can't be more than 4 m high, which rules out two storeys.
How long does a two-storey side extension take?
Allow 4 to 8 weeks for survey and design, then the approval period (councils aim to decide local applications within an average of 15 weeks; many take longer), then 4 to 8 weeks of technical design, which can overlap. The build itself usually takes 14 to 20 weeks, longer for large or complex designs.
How much does a two-storey side extension cost in Bangor (County Down)?
Our guide for Northern Ireland, which covers Bangor (County Down), is £1,800–£2,420 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £76,000–£101,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.
Can I build a two-storey side extension over my driveway?
Yes, if the drive is wide enough for a useful room and the council accepts the design. You may lose off-road parking, which some councils weigh up, and the foundations need to suit the ground below. We check parking, drains and meter positions at the free site visit before any drawings are prepared.
Nearby
The same service in neighbouring towns:
Other extensions in Bangor (County Down)
- Rear
- Wraparound
- Part two-storey
- Over a garage
- First floor
- Semi-detached
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Bangor (County Down) · Two-storey side extensions across County Down
The quickest next step is a visit. We'll look at your house in Bangor (County Down) and give you an honest view of the options.