Part single, part two-storey extensions in Kilbirnie

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

Postcode districts: KA14 and KA25
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: Beith (2 miles), Dalry (3.1 miles), Kilwinning (6.8 miles)
Distance to Kilmarnock: about 12.2 miles
First visit: Free, no obligation

About a part single, part two-storey extension

A part single, part two-storey extension is an extension where the ground floor is wider or deeper than the floor above, so only part of it rises to two storeys. It usually gives a large kitchen or living area with roof lights below and one bedroom or bathroom above. It is often a good way to add space while limiting the effect on neighbours.

We cover postcode districts KA14 and KA25 in and around Kilbirnie, along with neighbouring Beith, Dalry and Kilwinning.

What it costs in Kilbirnie

A guide price for Kilbirnie: 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). That works out at £1,880–£2,580 per m² of new floor space, including VAT at 20%. 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 Kilbirnie

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 Kilbirnie 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

Start at your house
We come to your home in Kilbirnie, 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.
Engineer it
Foundations sized for two floors, steels for any openings, and a building warrant, all before anyone starts on site.
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 Kilbirnie

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

Our guide for Scotland, which covers Kilbirnie, 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.

Who handles building standards for a project in Kilbirnie?

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.

Which postcodes do you cover around Kilbirnie?

We cover Kilbirnie (KA14 and KA25) and nearby places including Beith, Dalry and Kilwinning, plus the rest of Ayrshire. The first site visit is free.

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.

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.

Nearby

Other towns near Kilbirnie:

Other extensions in Kilbirnie

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

Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Kilbirnie.