Dunoon · Argyll and Bute

First-floor extensions in Dunoon

For a first-floor extension in Dunoon, 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.

We take on projects in Dunoon by arrangement. Site visits here aren't free as standard, and we'll agree travel costs with you in writing first.

The basics for Dunoon at a glance.

Postcode districts
PA22 and PA23
County / area
Argyll and Bute, 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
Gourock (4.3 miles), Greenock (6.4 miles), Helensburgh (8.7 miles)
Distance to Helensburgh
about 8.7 miles
First visit
By arrangement

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, a building warrant and the build, managed by us and carried out by vetted teams working under S&K.

Dunoon sits about 8.7 miles from Helensburgh. Closer to home, Gourock is 4.3 miles away and Greenock 6.4 miles.

What it costs in Dunoon

In Scotland, which includes Dunoon, we'd expect a first-floor extension to cost around £23,500–£34,000 for 4 m × 3.5 m of new first-floor space (14 m²), or £1,690–£2,440 per m² including VAT. These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.

SpecPer m²4 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 Dunoon

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 Dunoon 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

  1. Visit by arrangement

    We agree a visit to your home in Dunoon and any travel costs with you in writing first, then look at the structure, access and boundaries.

  2. Plans, then approval

    Measured survey, design, then the right approval route for your house. We explain each step before we take it.

  3. Fixed price in writing

    With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.

  4. On site

    One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.

Questions about first-floor extensions in Dunoon

Which postcodes do you cover around Dunoon?

We cover Dunoon (PA22 and PA23) and nearby places including Gourock, Greenock and Helensburgh, plus the rest of Argyll and Bute. Visits and projects in Dunoon are by arrangement, with travel costs agreed in writing first.

How much does a first-floor extension cost in Dunoon?

Our guide for Scotland, which covers Dunoon, 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.

How long does a first-floor extension 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 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

We also cover places near Dunoon, including:

Other extensions in Dunoon

All two-storey extension services in Dunoon · First-floor extensions 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 Dunoon.

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