Dungiven · County Londonderry

First-floor extensions in Dungiven

For a first-floor extension in Dungiven, the first questions are always the same: how big, which approvals, and what it will cost. This page answers all three for County Londonderry.

Useful details for planning a first-floor extension in Dungiven.

Postcode districts
BT49
County / area
County Londonderry, Northern Ireland
Price region
Northern Ireland
Guide price
£22,000–£32,000 (£1,580–£2,290 per m²)
Approval route
It may be permitted development if it goes no more than 3 m beyond the original rear wall and stays 7 m from the rear boundary.
Nearest towns
Limavady (8.2 miles), Maghera (11.5 miles), Eglinton (12 miles)
Distance to Derry
about 16.2 miles
First visit
Free, no obligation

About a first-floor extension

A first-floor extension is a new upstairs room built on top of an existing single-storey part of your house, such as a rear kitchen extension, a utility or a side annexe. It adds a bedroom, bathroom or study without enlarging the footprint. Whether it works depends mainly on whether the walls and foundations below can carry the extra load.

We cover Dungiven (BT49) and the places around it, including Limavady (8.2 miles), Maghera (11.5 miles) and Eglinton.

What it costs in Dungiven

A guide price for Dungiven: around £22,000–£32,000 for 4 m × 3.5 m of new first-floor space (14 m²). That works out at £1,580–£2,290 per m² of new floor space, including VAT at 20%. Professional fees for drawings and the structural engineer are listed separately on our prices page.

SpecPer m²4 m × 3.5 m of new first-floor space (14 m²)
Essential£1,460–£2,100 per m²£20,500–£29,500
Standard£1,580–£2,290 per m²£22,000–£32,000
Premium£1,900–£2,750 per m²£26,500–£38,500

Planning and building control in Dungiven

In Northern Ireland, a first floor over a rear extension can be permitted development if the extension goes no more than 3 m beyond the original rear wall and stays at least 7 m from the rear boundary, with height, materials and roof pitch conditions. Over a side extension, or beyond these limits, a planning application costs £347 per dwelling.

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 Dungiven homes

Can the existing structure take it?

Many single-storey extensions were built with foundations, walls and lintels sized for one storey. We find out what is there with trial holes and, where available, the original building control drawings. The engineer then decides whether to reuse, strengthen or rebuild parts of the structure.

Tying into the house

The new floor and walls must line up with the existing first floor, often through a new opening in the rear wall above the old one. Floor levels, the position of upstairs windows and the existing roof all affect where the opening can go, so we survey both floors carefully.

How we'd run your project

  1. Start at your house

    We come to your home in Dungiven, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.

  2. Design and approvals

    We draw the extension and check it against the rules for Northern Ireland, then apply for planning permission or a certificate of lawfulness, whichever fits.

  3. Engineer it

    Foundations sized for two floors, steels for any openings, and building control approval, all before anyone starts on site.

  4. Build and hand over

    We manage the build from groundworks to decoration-ready finish and hand over with the completion paperwork.

Questions about first-floor extensions in Dungiven

How much does a first-floor extension cost in Dungiven?

Our guide for Northern Ireland, which covers Dungiven, is £1,580–£2,290 per m² including VAT. A typical project with 4 m × 3.5 m of new first-floor space (14 m²) comes to about £22,000–£32,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

How long does a first-floor 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.

Do I need planning permission for a first-floor extension in Dungiven?

Dungiven is in Northern Ireland. It may be permitted development if it goes no more than 3 m beyond the original rear wall and stays 7 m from the rear boundary.

Can I build on top of my existing single-storey extension?

Often yes, but only after the structure has been checked. Foundations, walls and lintels built for one storey may not carry two. We dig trial holes, look for the original building control approval and ask the structural engineer to confirm what can stay, what needs strengthening and what must be rebuilt.

What happens to the room below while the first floor is built?

The old roof is removed, so the room below is exposed for a short period. We fit temporary weather protection, plan the work so the roof comes off only when the new structure is ready, and agree with you which rooms will be out of use and for roughly how long.

Nearby

Close to Dungiven? We work across the area, including:

Other extensions in Dungiven

All two-storey extension services in Dungiven · First-floor extensions across County Londonderry

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