First-floor extensions in Fort William
Our first-floor extensions service in Fort William covers everything: measured survey, design, planning or permitted development checks, structural design, building control and the build itself.
Fort William 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.
Fort William: the key facts for this kind of project.
- Postcode districts
- PH33, PH49 and PH50
- County / area
- The Highlands, Moray and Islands, 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
- Caol (1.5 miles), Oban (30.9 miles), Pitlochry (52.7 miles)
- Distance to Inverness
- about 56.6 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.
We cover postcode districts PH33, PH49 and PH50 in and around Fort William, along with neighbouring Caol, Oban and Pitlochry.
What it costs in Fort William
A guide price for Fort William: around £23,500–£34,000 for 4 m × 3.5 m of new first-floor space (14 m²). That works out at £1,690–£2,440 per m² of new floor space, including VAT at 20%. Design fees, structural calculations and approval fees are separate and listed on our prices page.
| Spec | Per m² | 4 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 Fort William
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 Fort William homes
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.
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.
How we'd run your project
Visit by arrangement
We agree a visit to your home in Fort William 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.
Structure and building standards
A structural engineer sizes the foundations and steels, and we get a building warrant before work starts.
Build
Foundations, walls, floor, roof, windows, then first and second fix. We break through into the house as late as we can.
Questions about first-floor extensions in Fort William
Who handles building standards for a project in Fort William?
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.
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.
Which postcodes do you cover around Fort William?
We cover Fort William (PH33, PH49 and PH50) and nearby places including Caol, Oban and Pitlochry, plus the rest of the Highlands, Moray and Islands. Visits and projects in Fort William are by arrangement, with travel costs agreed in writing first.
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 Fort William, including:
Other extensions in Fort William
- Rear
- Side
- Wraparound
- Part two-storey
- Over a garage
- Semi-detached
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Fort William · First-floor extensions across the Highlands, Moray and Islands
Send us your postcode and a few details. We'll get back to you to arrange a visit and talk through your options.