Two-storey extensions for detached houses in Rothesay
For a two-storey extension for a detached house in Rothesay, 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.
Rothesay 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.
Rothesay: the key facts for this kind of project.
- Postcode districts
- PA20 and PA21
- 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
- Largs (8 miles), Dunoon (9.3 miles), Gourock (12.6 miles)
- Distance to Helensburgh
- about 17.3 miles
- First visit
- By arrangement
About a two-storey extension for a detached house
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.
We cover Rothesay (PA20 and PA21) and the places around it, including Largs (8.0 miles), Dunoon (9.3 miles) and Gourock.
What it costs in Rothesay
Expect a two-storey extension for a detached house in Rothesay to land somewhere around £81,000–£108,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). Our Scotland guide rate is £1,930–£2,580 per m², including VAT. Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.
| 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 Rothesay
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 Rothesay 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 Rothesay and any travel costs with you in writing first, then look at the structure, access and boundaries.
Choose the approval route
Some designs fit permitted development, most need a householder application. We decide which applies in Scotland before drawing in detail.
Detail and price
Construction drawings, engineer's calculations and building warrant approval, then a written fixed price for the build.
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 Rothesay
Which postcodes do you cover around Rothesay?
We cover Rothesay (PA20 and PA21) and nearby places including Largs, Dunoon and Gourock, plus the rest of Argyll and Bute. Visits and projects in Rothesay are by arrangement, with travel costs agreed in writing first.
How much does a two-storey extension for a detached house cost in Rothesay?
Our guide for Scotland, which covers Rothesay, 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.
How long does a two-storey extension for a detached house take?
Allow 4 to 8 weeks for survey and design, then the approval period (councils have two months to decide a local planning application), 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.
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.
Nearby
Close to Rothesay? We work across the area, including:
Other extensions in Rothesay
- 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 Rothesay · Two-storey extensions for detached houses across Argyll and Bute
Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Rothesay.