What is a single-storey extension?
A single-storey extension is a ground-floor addition, usually at the rear of a house, that enlarges a kitchen, living or dining space. Most are built with cavity walls on concrete foundations and finished with a flat roof and roof lantern or a pitched tiled roof.
How much does a single-storey extension cost in Troon?
In Troon, a single-storey extension typically costs £1,900–£2,800 per m² of floor area, including VAT at 20% (standard rate). For a typical 20 m² project that is roughly £38,000–£56,000. Building costs in Scotland are close to the UK average, so the figures for Troon are close to our national guide. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (14 m²) | £26,500–£39,000 |
| Typical project (20 m²) | £38,000–£56,000 |
| Larger project (28 m²) | £53,000–£78,500 |
| Rate per m² | £1,900–£2,800 |
Your quote will depend mainly on:
- Kitchen, flooring and finishes, which we can include or leave to you
- Ground conditions and foundation depth
- How much of the existing house is opened up
- Floor area and the length of new wall
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a single-storey extension in Troon?
Before anything is built in Troon, we confirm which approvals apply in Scotland. In Scotland a single-storey extension is often permitted development (Class 1A): where any part is within 1 metre of a boundary, it can project up to 3 metres from the rear wall of a terraced house or 4 metres on other houses, with eaves no higher than 3 metres, an overall height of 4 metres and no more than half the front or rear garden covered. The rights do not apply in conservation areas or to flats, and a building warrant will usually still be needed before work starts.
Scotland has no Party Wall Act. Work on shared walls is governed by your title deeds, the Tenements (Scotland) Act 2004 for flats, and common law, so we agree arrangements with neighbours in writing before work starts.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
On a typical single-storey extension we handle:
- Foundations, drainage and any build-over agreement
- Measured survey and design drawings
- Structural calculations for steels and lintels
- Doors, windows and roof glazing installed
- Building control inspections and completion certificate
- Cavity walls, insulation and roof to current building regulations
How long does it take?
Allow 10 to 14 weeks on site for a typical rear extension, after approvals. Design and approvals come first and typically take 6 to 12 weeks, depending on the approval route.
Building in Troon
Scotland’s housing ranges from sandstone tenements and villas to post-war and modern estates, and the building warrant system shapes how projects are planned.
Projects in Troon (KA10) are surveyed in person before we quote, so the price reflects your actual property.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about single-storey extensions in Troon
How long does a single-storey extension take?
Once approvals are in place, a typical rear extension takes 10 to 14 weeks on site. Design and approvals usually take another 6 to 12 weeks beforehand, depending on whether a planning application is needed.
Do I need planning permission for a single-storey extension in Troon?
In Scotland a single-storey extension is often permitted development (Class 1A): where any part is within 1 metre of a boundary, it can project up to 3 metres from the rear wall of a terraced house or 4 metres on other houses, with eaves no higher than 3 metres, an overall height of 4 metres and no more than half the front or rear garden covered. The rights do not apply in conservation areas or to flats, and a building warrant will usually still be needed before work starts.
How much does a single-storey extension cost in Troon?
In Troon, a single-storey extension typically costs £1,900–£2,800 per m² of floor area, including VAT at 20% (standard rate). A typical 20 m² project comes to roughly £38,000–£56,000. Your fixed price depends on the survey and drawings.
Who approves a single-storey extension in Troon?
Planning matters in Troon go to the council covering your address, and the work needs a building warrant. We prepare and submit the applications for you.
Is VAT charged on an extension?
Yes. Building work on an existing home is standard-rated, so VAT at 20% applies. Our guide prices include it.
What is a build-over agreement?
If a public sewer runs within 3 metres of the extension, the water company normally has to agree to the work before it starts. We check sewer records during design and apply where needed.