Two-storey side extensions in New Buildings
Homes in New Buildings with a bit of space to the side or rear can often take a two-storey side extension. We'll tell you honestly whether yours can, and what approvals it needs.
Before you start in New Buildings, here's what applies.
- Postcode districts
- BT48
- County / area
- County Londonderry, 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
- Derry (3.2 miles), Culmore (7.1 miles), Eglinton (7.9 miles)
- Distance to Derry
- about 3.1 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 New Buildings (BT48) and the places around it, including Derry (3.2 miles), Culmore (7.1 miles) and Eglinton.
What it costs in New Buildings
In Northern Ireland, which includes New Buildings, we'd expect a two-storey side extension to cost around £76,000–£101,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space), or £1,800–£2,420 per m² including VAT. Design fees, structural calculations and approval fees are separate and listed on our prices page.
| 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 New Buildings
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 New Buildings homes
Set-down and set-back
Councils usually want a two-storey side extension to look subordinate to the house. Setting the front wall back from the main front and dropping the ridge slightly below the main roof helps it read as an addition, and is often expected in local design guidance.
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
Measure and listen
A visit to New Buildings to understand how you live in the house now and what the extra rooms need to do, plus a first look at the structure.
Drawings and permission
Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering New Buildings.
Structure and building control
A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.
Build it
The new structure goes up first, then we open into the house, finish inside and get the completion certificate.
Questions about two-storey side extensions in New Buildings
Do I need planning permission for a two-storey side extension in New Buildings?
New Buildings 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 much does a two-storey side extension cost in New Buildings?
Our guide for Northern Ireland, which covers New Buildings, 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.
Which postcodes do you cover around New Buildings?
We cover New Buildings (BT48) and nearby places including Derry, Culmore and Eglinton, plus the rest of County Londonderry. The first site visit is free.
Who handles building control for a project in New Buildings?
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.
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 New Buildings
- 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 New Buildings · Two-storey side extensions across County Londonderry
Tell us about your house in New Buildings and we'll call you back to arrange a free, no-obligation visit.