Cumbernauld · Lanarkshire

Part single, part two-storey extensions in Cumbernauld

A part single, part two-storey extension is one of the most space-efficient ways to add bedrooms and living space to a house in Cumbernauld, because the new floors share one set of foundations and one roof.

Cumbernauld: the key facts for this kind of project.

Postcode districts
G67 and G68
County / area
Lanarkshire, 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
Kilsyth (3.3 miles), Moodiesburn (4.2 miles), Airdrie (5.6 miles)
Distance to East Kilbride
about 14.5 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.

We cover postcode districts G67 and G68 in and around Cumbernauld, along with neighbouring Kilsyth, Moodiesburn and Airdrie.

What it costs in Cumbernauld

A guide price for Cumbernauld: 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%. Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.

SpecPer m²A 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 Cumbernauld

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 Cumbernauld 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

  1. Understand the brief

    At your home in Cumbernauld we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.

  2. 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.

  3. Engineer it

    Foundations sized for two floors, steels for any openings, and a building warrant, all before anyone starts on site.

  4. On site

    One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.

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

Which postcodes do you cover around Cumbernauld?

We cover Cumbernauld (G67 and G68) and nearby places including Kilsyth, Moodiesburn and Airdrie, plus the rest of Lanarkshire. The first site visit is free.

How long does a part single, part two-storey 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 part single, part two-storey extension in Cumbernauld?

Cumbernauld 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.

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 Cumbernauld:

Other extensions in Cumbernauld

All two-storey extension services in Cumbernauld · Part single, part two-storey extensions across Lanarkshire

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