Single-storey rear extensions in Largs: design, approvals and build
Largs homeowners can use us for the whole single-storey extension project: survey, design, planning or permitted development checks, the building warrant and the build itself.
- Guide price in LargsFrom £20,500 inc VAT
- PlanningScottish householder rules; building warrant needed
- Build time10–16 weeks on site
- Postcode districtsKA30
Covering Largs
Site visits are available across Largs (KA30). The same team covers Saltcoats (11 miles), Kilwinning (12 miles), Irvine (15 miles), Troon (19 miles), all within easy reach.
Across Scotland, extensions follow Scottish planning and building standards, including the building warrant process, which we build into the programme from the start.
Single-storey extension prices in Largs
Labour and material costs vary across the UK, so for Largs we use our Scotland factor (×0.98). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Largs: £1,720 to £3,330 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £20,500 – £24,500 | £24,000 – £31,000 | £30,500 – £40,000 |
| 4 m × 5 m 20 m² | £34,000 – £40,500 | £40,000 – £51,000 | £50,500 – £67,000 |
| 5 m × 6 m 30 m² | £51,000 – £60,500 | £60,000 – £76,500 | £76,000 – £100,000 |
Want a range for your exact size? The guide-price tool takes about a minute.
Will the council need to approve it?
In Scotland, householder permitted development rules (Class 1A for single-storey ground-floor extensions and Class 1B for extensions of more than one storey) allow some smaller extensions without a planning application, within limits on depth, height and distance from the boundary. Conservation areas and listed buildings are more restricted. Separately, almost every extension needs a building warrant from the council before work starts.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
Scotland has no Party Wall Act. Where work affects a shared wall or a neighbour's land, we agree access, protection and making good with your neighbour in writing before work starts.
Applications are decided by your council as planning authority.
What we take care of
- Walls, steel beams and the new opening into the house
- Building regulations drawings and structural calculations
- Planning route checked and the right approval obtained
- Doors, windows, insulation, plastering and first fix to finish
- Flat or pitched roof, rooflights or lantern
- Foundations, drainage and groundworks
Depth is the big decision. Every extra metre adds floor area but also takes garden and can push you out of permitted development. We draw the room at two or three depths so you can see the trade-off in space, light and cost before anything is fixed.
From first visit to completion
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Your questions about a single-storey extension in Largs
Do you cover all of Largs?
Yes. We cover Largs and the surrounding parts of Ayrshire. Site visits are free and there is no obligation.
Will my neighbours in Largs be involved?
If a planning application is needed, the council notifies neighbours. Where work is close to a shared boundary, we agree access and protection with them in writing.
How long does a single-storey extension take to build in Largs?
On site, typically 10 to 16 weeks once approvals are in place. Before that, allow 4–12 weeks design and approvals.
Will I need a steel beam?
Almost always. Opening up the rear wall to join the new room to the house needs a beam, usually steel, sized by a structural engineer. It is included in our quotes.
Can I stay in the house during the build?
Usually yes. Most of the work happens outside until the final weeks, when we open the rear wall. We plan that stage carefully and seal the opening with a temporary screen to keep dust down.
Book a free site visit in Largs
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.