Two-storey extensions for detached houses in Isle of Islay
For a two-storey extension for a detached house in Isle of Islay, the first questions are always the same: how big, which approvals, and what it will cost. This page answers all three for Argyll and Bute.
Isle of Islay is outside our usual mainland visit area, so visits and projects here are by arrangement. We'll agree any travel costs with you before anything is booked.
Quick reference for homeowners in Isle of Islay.
- Postcode districts
- PA43, PA44, PA45, PA46, PA48 and PA49
- County / area
- Argyll and Bute, Scotland
- Price region
- Scotland
- Guide price
- £81,000–£108,500 (£1,930–£2,580 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
- Isle of Mull (49.1 miles), Campbeltown (35 miles), Lochgilphead (35.8 miles)
- Distance to Helensburgh
- about 60.5 miles
- First visit
- By arrangement
About a two-storey extension for a detached house
A two-storey extension for a detached house is a two-floor addition to the side, rear or both of a house that stands on its own plot. Detached houses often have room on more than one side, so there is more choice of layout and fewer shared-wall issues. The design still needs to respect boundaries, neighbours' windows and the look of the house.
Isle of Islay sits about 60.5 miles from Helensburgh. Closer to home, Isle of Mull is 49.1 miles away and Campbeltown 35.0 miles.
What it costs in Isle of Islay
Using our Scotland rates, a two-storey extension for a detached house with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £81,000–£108,500, including VAT. Bigger or more glazed designs cost more per m². Design fees, structural calculations and approval fees are separate and listed on our prices page.
| Spec | Per m² | A 3 m × 7 m footprint on two floors (42 m² of new floor space) |
|---|---|---|
| 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 |
Planning and building standards in Isle of Islay
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.
Design points for Isle of Islay homes
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.
Choosing the best side
On a detached house you can often extend on either side or the rear. We look at orientation for daylight, where the stairs and landing are, the distance to each boundary, drains and trees, so the extension goes where it adds the most useful space.
How we'd run your project
Visit by arrangement
We agree a visit to your home in Isle of Islay and any travel costs with you in writing first, then look at the structure, access and boundaries.
Get it approved
Once you're happy with the design we submit it to the council for Isle of Islay 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.
On site
One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.
Questions about two-storey extensions for detached houses in Isle of Islay
How much does a two-storey extension for a detached house cost in Isle of Islay?
Our guide for Scotland, which covers Isle of Islay, is £1,930–£2,580 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £81,000–£108,500. 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 extension for a detached house in Isle of Islay?
Isle of Islay 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 Isle of Islay?
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.
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.
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.
Nearby
We also cover places near Isle of Islay, including:
Other extensions in Isle of Islay
- Rear
- Side
- Wraparound
- Part two-storey
- Over a garage
- First floor
- Semi-detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Isle of Islay · Two-storey extensions for detached houses across Argyll and Bute
Send us your postcode and a few details. We'll get back to you to arrange a visit and talk through your options.