First-floor extensions in Magherafelt
Our first-floor extensions service in Magherafelt covers everything: measured survey, design, planning or permitted development checks, structural design, building control and the build itself.
The basics for Magherafelt at a glance.
- Postcode districts
- BT45
- 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
- Maghera (6.8 miles), Cookstown (9.4 miles), Randalstown (12.2 miles)
- Distance to Derry
- about 32.6 miles
- First visit
- Free, no obligation
About a first-floor extension
A first-floor extension suits you if your house already has a single-storey extension and you need more space upstairs. You get a structural check of the existing walls and foundations, a design that ties the new floor into the house, the approvals your nation needs, building regulations approval and the build, managed by us and carried out by vetted teams working under S&K.
Magherafelt sits about 32.6 miles from Derry. Closer to home, Maghera is 6.8 miles away and Cookstown 9.4 miles.
What it costs in Magherafelt
For budgeting in Magherafelt, allow around £22,000–£32,000 for a first-floor extension with 4 m × 3.5 m of new first-floor space (14 m²). That's based on £1,580–£2,290 per m² including VAT for Northern Ireland. Design fees, structural calculations and approval fees are separate and listed on our prices page.
| Spec | Per m² | 4 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 Magherafelt
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 Magherafelt homes
Escape and fire safety
A new first-floor bedroom needs an escape window with a clear opening of at least 0.33 m², at least 450 mm wide and 450 mm high, with the bottom no more than 1,100 mm above the floor, unless there is a protected route to the stairs.
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.
How we'd run your project
Measure and listen
A visit to Magherafelt to understand how you live in the house now and what the extra rooms need to do, plus a first look at the structure.
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.
Detail and price
Construction drawings, engineer's calculations and building control sign-off, then a written fixed price for the build.
Finish and certify
Second fix, plastering and making good, then building control's final inspection and the completion paperwork.
Questions about first-floor extensions in Magherafelt
Which postcodes do you cover around Magherafelt?
We cover Magherafelt (BT45) and nearby places including Maghera, Cookstown and Randalstown, plus the rest of County Londonderry. The first site visit is free.
Do I need planning permission for a first-floor extension in Magherafelt?
Magherafelt 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.
How much does a first-floor extension cost in Magherafelt?
Our guide for Northern Ireland, which covers Magherafelt, 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.
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.
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.
Nearby
The same service in neighbouring towns:
Other extensions in Magherafelt
- Rear
- Side
- Wraparound
- Part two-storey
- Over a garage
- Semi-detached
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Magherafelt · First-floor extensions across County Londonderry
The quickest next step is a visit. We'll look at your house in Magherafelt and give you an honest view of the options.