First-floor extensions in Irvine

Before you start in Irvine, here's what applies.

Postcode districts: KA11 and KA12
County / area: Ayrshire, 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: Kilwinning (3.1 miles), Stevenston (4.1 miles), Saltcoats (5.2 miles)
Distance to Kilmarnock: about 6.2 miles
First visit: Free, no obligation

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.

Around Irvine we also work in Kilwinning, Stevenston and Saltcoats, and across the rest of Ayrshire. Postcode districts in and near Irvine: KA11 and KA12.

What it costs in Irvine

Guide prices for first-floor extensions in Scotland are around £1,690–£2,440 per m² of new floor space, including VAT. For a typical project with 4 m × 3.5 m of new first-floor space (14 m²), that's roughly £23,500–£34,000. Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.

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 Irvine

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 Irvine 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.

Replacing the flat roof

The existing roof usually comes off and is replaced by a new first-floor structure. The room below is exposed for a short time, so we plan temporary weatherproofing and sequence the work to keep the kitchen or living room usable for as long as possible.

How we'd run your project

Start at your house
We come to your home in Irvine, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
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 Irvine

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.

Do I need planning permission for a first-floor extension in Irvine?

Irvine 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.

Which postcodes do you cover around Irvine?

We cover Irvine (KA11 and KA12) and nearby places including Kilwinning, Stevenston and Saltcoats, plus the rest of Ayrshire. The first site visit is free.

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.

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.

Nearby

Nearby towns we cover for first-floor extensions:

Other extensions in Irvine

All two-storey extension services in Irvine · First-floor extensions across Ayrshire

Want a figure first? Try our guide price tool, then book a free visit to firm it up.