Two-storey extensions for detached houses in Dumfries and Galloway
If you're in Dumfries and Galloway and weighing up a two-storey extension for a detached house, start here: guide costs for Scotland, the approvals you'll need and how we work.
Dumfries and Galloway at a glance
- Nation
- Scotland
- Price region
- Scotland
- Postcode areas
- DG
- Towns covered
- 11 listed below, plus surrounding villages
- 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.
- Site visits
- Free, no obligation
What a two-storey extension for a detached house involves
This service suits you if you own a detached house and want a substantial amount of extra space, whether a side extension over a drive, a rear extension into the garden or a wraparound. You get a survey of the whole plot, options that compare layouts and costs, the approvals your nation needs, structural design and the build, carried out by vetted teams working under S&K.
The main places we list in Dumfries and Galloway are Dumfries (DG1), Stranraer (DG9), Annan (DG12), Locharbriggs (DG1), Dalbeattie (DG5) and Lockerbie (DG11). We cover the villages in between too.
Guide price in Scotland
Most of the cost of a two-storey extension for a detached house is set by its size and specification. For Dumfries and Galloway and the rest of Scotland, our guide is £1,930–£2,580 per m² including VAT, so about £81,000–£108,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). Steelwork for wide openings is the item most likely to move the figure; we'll know once the engineer has designed it.
| Spec | Per m² | Typical project |
|---|---|---|
| Essential | £1,770–£2,380 per m² | £74,500–£100,000 |
| Standard | £1,930–£2,580 per m² | £81,000–£108,500 |
| Premium | £2,310–£3,100 per m² | £97,000–£130,500 |
Rules in Scotland
In Scotland, a detached house on a large plot may be able to use Class 1B permitted development if no part of the two-storey extension is within 10 m of any boundary, it is no higher than the house and is not in a conservation area. Otherwise a householder application costs £371. A building warrant is needed either way.
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.
There is no Party Wall Act in Scotland. Shared walls and boundaries are governed by title deeds and common law, so we speak to neighbours early and record the condition of shared structures.
Getting the design right
Larger spans and steelwork
Bigger extensions often mean wider openings and longer spans, which need more steel and sometimes a steel frame. The engineer designs these early, because the size of the steel affects ceiling heights, floor depths and the cost.
Keeping it subordinate
Large detached houses can take a large extension, but councils still expect it to look secondary to the main house. A lower ridge, a modest set-back at the front and matching materials keep the proportions right, even on a wide plot.
How we work in Dumfries and Galloway
Visit and first ideas
One of our team visits your house in Dumfries and Galloway, checks the walls, roof and drains, and sketches out options with you.
Choose the approval route
Some designs fit permitted development, most need a householder application. We decide which applies in Scotland before drawing in detail.
Engineer it
Foundations sized for two floors, steels for any openings, and a building warrant, all before anyone starts on site.
Build
Foundations, walls, floor, roof, windows, then first and second fix. We break through into the house as late as we can.
Towns we cover in Dumfries and Galloway
- Dumfries
- Stranraer
- Annan
- Locharbriggs
- Dalbeattie
- Lockerbie
- Castle Douglas
- Newton Stewart
- Cairnryan
- Kirkcudbright
- Gretna
Two-storey extensions for detached houses in Dumfries and Galloway: questions
How much does a two-storey extension for a detached house cost in Dumfries and Galloway?
In Scotland our guide is £1,930–£2,580 per m² including VAT, so about £81,000–£108,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). Essential and Premium specs move that by roughly 8% down or 20% up.
Can I extend a detached house on both sides?
Sometimes. With planning permission, a council may accept extensions on both sides if the house stays well proportioned and keeps gaps to the boundaries. It is more common to extend on one side and the rear, or with a wraparound. We look at the plot as a whole before suggesting more than one extension.
Is a detached house extension a better investment than moving?
It often costs less than the gap between your house and a larger one nearby, once property tax, legal fees and removal costs are counted, but that depends on your area. Extending also has limits: every street has a ceiling price. We give you build costs so you can compare them with local asking prices.
Will I need planning permission in Dumfries and Galloway?
Dumfries and Galloway 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.
Neighbouring areas
- Two-storey extensions for detached houses in Cumbria
- Two-storey extensions for detached houses in Ayrshire
- Two-storey extensions for detached houses in Lanarkshire
- Two-storey extensions for detached houses in the Scottish Borders
All extension services in Dumfries and Galloway · About two-storey extensions for detached houses
Ready to see what a second storey could do for your home?
Book a free site visit. We'll look at your house, talk through options and explain the approvals you'd need, then price the design stage in writing.