Part single, part two-storey extensions in Kilmarnock

What we'd confirm first for a project in Kilmarnock.

Postcode districts: KA1, KA2, KA3, KA4, KA16 and KA17
County / area: Ayrshire, Scotland
Price region: Scotland
Guide price: £67,500–£93,000 (£1,880–£2,580 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: Stewarton (4.8 miles), Irvine (6.2 miles), Troon (8.1 miles)
First visit: Free, no obligation

About a part single, part two-storey extension

A part single, part two-storey extension suits you if you want a generous ground floor but only need one extra room upstairs, or if a full two-storey design would affect a neighbour too much. You get design options that test where the two-storey part works best, the approvals your nation needs, structural design, a building warrant and the build, carried out by vetted teams working under S&K.

Around Kilmarnock we also work in Stewarton, Irvine and Troon, and across the rest of Ayrshire. Postcode districts in and near Kilmarnock: KA1, KA2, KA3, KA4, KA16 and KA17.

What it costs in Kilmarnock

In Scotland, which includes Kilmarnock, we'd expect a part single, part two-storey extension to cost around £67,500–£93,000 for a 6 m × 4 m ground floor and a first floor over half of it (36 m² in total), or £1,880–£2,580 per m² including VAT. These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.

Spec	Per m²	A 6 m × 4 m ground floor and a first floor over half of it (36 m² in total)
Essential	£1,730–£2,380 per m²	£62,500–£85,500
Standard	£1,880–£2,580 per m²	£67,500–£93,000
Premium	£2,260–£3,100 per m²	£81,000–£111,500

Planning and building standards in Kilmarnock

In Scotland, because part of the extension is more than one storey, it is assessed under Class 1B, which needs at least 10 m to every boundary for permitted development. On most plots that is not possible, so the extension needs a householder application (£371, decided within two months). A building warrant is also needed before any 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 Kilmarnock homes

Structure at the step

The first-floor wall above often sits over the new open-plan space, so it needs a steel beam or frame to carry it. Loads come down at different points than in a full two-storey design, and the engineer sizes the foundations to suit each part.

Where to put the two-storey part

The two-storey section usually works best away from the closest neighbour, with the single-storey part on that boundary side. We test a few positions against neighbours' windows, the upstairs layout and the roof shape before choosing the one to take forward.

How we'd run your project

Understand the brief
At your home in Kilmarnock we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.
Choose the approval route
Some designs fit permitted development, most need a householder application. We decide which applies in Scotland before drawing in detail.
Price it properly
Once the engineer's calculations are in, we fix the build price in writing, with a clear list of what's included.
Build it
The new structure goes up first, then we open into the house, finish inside and get the completion certificate.

Questions about part single, part two-storey extensions in Kilmarnock

Do I need planning permission for a part single, part two-storey extension in Kilmarnock?

Kilmarnock 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 Kilmarnock?

We cover Kilmarnock (KA1, KA2, KA3, KA4, KA16 and KA17) and nearby places including Stewarton, Irvine and Troon, plus the rest of Ayrshire. The first site visit is free.

How much does a part single, part two-storey extension cost in Kilmarnock?

Our guide for Scotland, which covers Kilmarnock, is £1,880–£2,580 per m² including VAT. A typical project with a 6 m × 4 m ground floor and a first floor over half of it (36 m² in total) comes to about £67,500–£93,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Which side should the two-storey part go on?

Usually the side furthest from the nearest neighbour's windows, so the single-storey part sits nearest them and keeps their light. Other factors are where the stairs land upstairs, which room needs the extra space and where drains run. We sketch options at the design stage and explain which is most likely to be approved.

Can the single-storey part be deeper than the two-storey part?

With planning permission, yes, and that is often the point of the design: the ground floor projects further into the garden while the first floor stays back from neighbours. Under permitted development, the depth limits for extensions of more than one storey can apply to the whole extension, so we confirm which route applies before drawings are finalised.

Nearby

Close to Kilmarnock? We work across the area, including:

Other extensions in Kilmarnock

All two-storey extension services in Kilmarnock · Part single, part two-storey extensions across Ayrshire

Send us your postcode and a few details. We'll get back to you to arrange a visit and talk through your options.