Largs, Ayrshire
Single-storey rear extension in Largs
For homes in Largs, a single-storey rear extension is often the simplest way to gain space without moving. Ground-floor space across the back of the house, usually for a kitchen, dining or family room. We take it from survey to completion certificate.
We cover Largs (KA30) as part of our Ayrshire work. A depth of 3 to 4 metres keeps many single-storey rear extensions in Largs within permitted development, subject to the house's planning history.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a single-storey rear extension cost in Largs?
In Largs, our guide for a single-storey rear extension is £1,800–£2,940 per square metre including VAT for a standard specification. Prices in Scotland sit a little below our West Midlands baseline; building warrant fees and drawings are budgeted separately.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £21,500–£35,500 |
| 4 m wide × 5 m deep (20 m²) | £36,000–£59,000 |
| 4 m wide × 6 m deep (24 m²) | £43,500–£70,500 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission for a single-storey rear extension in Largs?
Planning for a single-storey rear extension in Largs follows the Scottish householder rules.
Scottish householder permitted development (Class 1A) covers many single-storey rear extensions, with a 3 metre eaves limit, a 4 metre height limit and, within 1 metre of a boundary, a depth limit of 3 metres for terraced houses or 4 metres for others. Conservation areas are excluded, and you need a building warrant whatever the planning position.
Scotland has no larger-extension prior approval route; extensions beyond permitted development need a planning application.
Classes 1A and 1B do not apply in conservation areas, and listed buildings need listed building consent. At the first visit we measure what is there now and tell you which route fits: permitted development or a planning application, plus the building warrant.
What are homes in Largs like to extend?
Post-war semis and terraces are common around Largs, and many have room for a single-storey rear extension within Class 1A limits.
How a single-storey rear extension in Largs comes together
Survey visit
We visit free of charge, measure up, check access, drainage and neighbours' extensions, and note what you want the room to do.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for the building warrant.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the accepted completion certificate and any guarantees from suppliers.
Single-storey rear extensions near Largs
Close by, we work in Ardrossan, about 10.3 miles away, and Greenock, about 11.2 miles away.
- Single-storey rear extension in Ardrossan
- Single-storey rear extension in Greenock
- Single-storey rear extension in Saltcoats
- Single-storey rear extension in Gourock
- Single-storey rear extension in Kilwinning
Other work in Largs:
FAQ
Single-storey rear extension questions in Largs
Is the site visit in Largs free?
Yes. We visit, measure up and talk through the options with no cost and no obligation.
Will I need a structural engineer?
Yes for the beam over the new opening and usually the foundations; we arrange them and their calculations go to building control.
Does it add value to the house?
Nationwide's October 2025 house price research found that a 10% increase in floor area is linked to about 5% higher value on average. It is a guide, not a promise; local agents can tell you what extended homes on your street sell for.
How much does a single-storey rear extension cost in Largs?
As a guide, £1,800–£2,940 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £21,500–£35,500 at that rate. Your written price follows the survey.
Do I need planning permission for a rear extension in Largs?
Many single-storey rear extensions are permitted development under Class 1A, but not in conservation areas; you always need a building warrant before work starts.
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.