Two-storey wraparound extensions in New Buildings

The basics for New Buildings at a glance.

Postcode districts: BT48
County / area: County Londonderry, Northern Ireland
Price region: Northern Ireland
Guide price: £106,000–£145,500 (£1,890–£2,600 per m²)
Approval route: Planning permission is usually needed.
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 wraparound extension

A two-storey wraparound extension suits a house with space both beside it and behind it, where you want to transform the layout rather than add a single room. You get one design for the whole L-shape, the planning application, structural design for the corner and the openings into the house, building regulations approval and the build, managed by us and carried out by vetted teams working under S&K.

We cover postcode district BT48 in and around New Buildings, along with neighbouring Derry, Culmore and Eglinton.

What it costs in New Buildings

Our guide for Northern Ireland is £1,890–£2,600 per m² including VAT. On a project with an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space), that puts a two-storey wraparound extension in New Buildings at roughly £106,000–£145,500. The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.

Spec	Per m²	An L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space)
Essential	£1,740–£2,390 per m²	£97,500–£133,500
Standard	£1,890–£2,600 per m²	£106,000–£145,500
Premium	£2,270–£3,120 per m²	£127,000–£174,500

Planning and building control in New Buildings

In Northern Ireland, the permitted development allowance for two-storey extensions covers rear extensions of up to 3 m that stay 7 m from the rear boundary. A wraparound adds a side element on two floors, so it normally needs a planning application. The fee is £347 per dwelling, and councils aim for an average of 15 weeks for local applications.

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

Two roofs that meet

A wraparound needs the side roof and rear roof to join cleanly, often with a valley or hip where they meet. Getting pitches and ridge heights right keeps rainwater moving and avoids a bulky mass at the back corner, which neighbours and planners notice.

Phasing the build

A wraparound touches two sides of the house at once, so the kitchen and often the rear rooms are out of use for part of the build. We plan the sequence so you keep a working kitchen and bathroom for as long as possible, or advise when moving out briefly makes sense.

How we'd run your project

Visit and first ideas
One of our team visits your house in New Buildings, checks the walls, roof and drains, and sketches out options with you.
Get it approved
Once you're happy with the design we submit it to the council for New Buildings and deal with any questions from the planning officer.
Price it properly
Once the engineer's calculations are in, we fix the build price in writing, with a clear list of what's included.
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 wraparound extensions in New Buildings

How much does a two-storey wraparound extension cost in New Buildings?

Our guide for Northern Ireland, which covers New Buildings, is £1,890–£2,600 per m² including VAT. A typical project with an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space) comes to about £106,000–£145,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Do I need planning permission for a two-storey wraparound extension in New Buildings?

New Buildings is in Northern Ireland. Planning permission is usually needed.

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.

Is a wraparound extension better than separate side and rear extensions?

Building both at once usually costs less than two separate projects, because you pay for one set-up, one scaffold, one roof junction and one set of approvals. It also lets the layout be designed as a whole. The trade-off is a larger single outlay and a longer build, often 16 to 24 weeks at this size.

Does a wraparound extension need steel?

Almost always. Opening the corner of the house and the old rear wall to make one open-plan space means steel beams, and often a steel post or frame at the outside corner. The structural engineer sizes these, and the steel is ordered once the design is fixed, which is one reason a wraparound needs careful sequencing.

Nearby

Nearby towns we cover for two-storey wraparound extensions:

Other extensions in New Buildings

All two-storey extension services in New Buildings · Two-storey wraparound extensions across County Londonderry

Want a figure first? Try our guide price tool, then book a free visit to firm it up.