First-floor extensions in Newton Mearns

Newton Mearns: the key facts for this kind of project.

Postcode districts: G77
County / area: Glasgow and Dunbartonshire, 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: Clarkston (2.4 miles), Giffnock (2.6 miles), Barrhead (2.9 miles)
Distance to Glasgow: about 7 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.

Newton Mearns sits about 7.0 miles from Glasgow. Closer to home, Clarkston is 2.4 miles away and Giffnock 2.6 miles.

What it costs in Newton Mearns

Our guide for Scotland is £1,690–£2,440 per m² including VAT. On a project with 4 m × 3.5 m of new first-floor space (14 m²), that puts a first-floor extension in Newton Mearns at roughly £23,500–£34,000. Keep a contingency of around 10% for things nobody can see until the ground is opened up.

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 Newton Mearns

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 Newton Mearns homes

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.

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'd run your project

Visit and first ideas
One of our team visits your house in Newton Mearns, checks the walls, roof and drains, and sketches out options with you.
Design and approvals
We draw the extension and check it against the rules for Scotland, then apply for planning permission or a certificate of lawfulness, whichever fits.
Technical design
We prepare the building warrant drawings, structural calculations and specification so the build price can be fixed.
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 Newton Mearns

Who handles building standards for a project in Newton Mearns?

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.

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

Newton Mearns 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.

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.

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

Close to Newton Mearns? We work across the area, including:

Other extensions in Newton Mearns

All two-storey extension services in Newton Mearns · First-floor extensions across Glasgow and Dunbartonshire

The quickest next step is a visit. We'll look at your house in Newton Mearns and give you an honest view of the options.