First-floor extensions in Argyll and Bute
From first sketch to completion certificate, we deliver first-floor extensions for homeowners across Argyll and Bute.
Argyll and Bute at a glance
- Nation
- Scotland
- Price region
- Scotland
- Postcode areas
- G, PA
- Towns covered
- 8 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 on the mainland; island and remote addresses by arrangement, with travel costs agreed first
What a first-floor extension involves
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.
Towns in Argyll and Bute include Helensburgh (G84), Dunoon (PA22), Oban (PA34), Rothesay (PA20), Campbeltown (PA28) and Isle of Islay (PA43). If yours isn't listed, we still cover it.
Guide price in Scotland
For budgeting in Argyll and Bute, allow around £23,500–£34,000 for a first-floor extension with 4 m × 3.5 m of new first-floor space (14 m²). That's based on £1,690–£2,440 per m² including VAT for Scotland. These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.
| Spec | Per m² | Typical project |
|---|---|---|
| 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 |
Rules in Scotland
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.
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
Tying into the house
The new floor and walls must line up with the existing first floor, often through a new opening in the rear wall above the old one. Floor levels, the position of upstairs windows and the existing roof all affect where the opening can go, so we survey both floors carefully.
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.
How we work in Argyll and Bute
Measure and listen
A visit to Argyll and Bute to understand how you live in the house now and what the extra rooms need to do, plus a first look at the structure.
Drawings and permission
Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Argyll and Bute.
Detail and price
Construction drawings, engineer's calculations and building warrant approval, then a written fixed price for the build.
Build it
The new structure goes up first, then we open into the house, finish inside and get the completion certificate.
Towns we cover in Argyll and Bute
First-floor extensions in Argyll and Bute: questions
How much does a first-floor extension cost in Argyll and Bute?
In Scotland our guide is £1,690–£2,440 per m² including VAT, so about £23,500–£34,000 for 4 m × 3.5 m of new first-floor space (14 m²). Essential and Premium specs move that by roughly 8% down or 20% up.
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.
Will I need planning permission in Argyll and Bute?
Argyll and Bute 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
- First-floor extensions in Renfrewshire and Inverclyde
- First-floor extensions in Ayrshire
- First-floor extensions in Glasgow and Dunbartonshire
- First-floor extensions in Lanarkshire
All extension services in Argyll and Bute · About first-floor extensions
Ready to see what a second storey could do for your home?
Book a site visit: free on the mainland, by arrangement on islands and remote addresses. We'll look at your house, talk through options and explain the approvals you'd need.