First-floor extensions in Dumfries
If you live in Dumfries and need more room without moving, a first-floor extension is worth a serious look. We handle the drawings, approvals, structure and build.
The basics for Dumfries at a glance.
- Postcode districts
- DG1 and DG2
- County / area
- Dumfries and Galloway, Scotland
- Price region
- Scotland
- Guide price
- £23,500–£34,000 (£1,690–£2,440 per m²)
- Approval route
- Planning permission is usually needed: Class 1B permitted development only applies if every part of the extension is at least 10 m from all boundaries. A building warrant is needed before work starts.
- Nearest towns
- Locharbriggs (2.6 miles), Lockerbie (10.7 miles), Dalbeattie (12.6 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 postcode districts DG1 and DG2 in and around Dumfries, along with neighbouring Locharbriggs, Lockerbie and Dalbeattie.
What it costs in Dumfries
Guide prices for first-floor extensions in Scotland are around £1,690–£2,440 per m² of new floor space, including VAT. For a typical project with 4 m × 3.5 m of new first-floor space (14 m²), that's roughly £23,500–£34,000. These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.
| Spec | Per m² | 4 m × 3.5 m of new first-floor space (14 m²) |
|---|---|---|
| Essential | £1,560–£2,250 per m² | £22,000–£31,500 |
| Standard | £1,690–£2,440 per m² | £23,500–£34,000 |
| Premium | £2,030–£2,930 per m² | £28,500–£41,000 |
Planning and building standards in Dumfries
In Scotland, permitted development for extensions of more than one storey (Class 1B) needs at least 10 m to every boundary and no part higher than the house. Most first-floor extensions cannot meet the 10 m test, so plan for a householder application (£371, decided within two months) and a building warrant before work starts.
Approval in Scotland: Householder planning application: £371. Councils have two months to decide a local planning application.
Building standards: A building warrant from the council's building standards service before work starts, and a completion certificate at the end. Scotland uses its own Technical Handbooks.
Design points for Dumfries 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 standards drawings. The engineer then decides whether to reuse, strengthen or rebuild parts of the structure.
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.
How we'd run your project
Understand the brief
At your home in Dumfries we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.
Design and approvals
We draw the extension and check it against the rules for Scotland, then apply for planning permission or a certificate of lawfulness, whichever fits.
Technical design
We prepare the building warrant drawings, structural calculations and specification so the build price can be fixed.
Finish and certify
Second fix, plastering and making good, then the council's final building standards inspection and the completion paperwork.
Questions about first-floor extensions in Dumfries
Do I need planning permission for a first-floor extension in Dumfries?
Dumfries is in Scotland. Planning permission is usually needed: Class 1B permitted development only applies if every part of the extension is at least 10 m from all boundaries. A building warrant is needed before work starts.
Who handles building standards for a project in Dumfries?
We handle it as part of the project. What's needed in Scotland: a building warrant from the council's building standards service before work starts, and a completion certificate at the end. Scotland uses its own Technical Handbooks. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.
How much does a first-floor extension cost in Dumfries?
Our guide for Scotland, which covers Dumfries, is £1,690–£2,440 per m² including VAT. A typical project with 4 m × 3.5 m of new first-floor space (14 m²) comes to about £23,500–£34,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.
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 a building warrant 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
Nearby towns we cover for first-floor extensions:
Other extensions in Dumfries
- 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 Dumfries · First-floor extensions across Dumfries and Galloway
Book a free site visit in Dumfries and we'll tell you what's possible, what approvals you need and what the design stage would cost.