Side extensions in Helensburgh: design, approvals and build
Our design and build teams take on side extensions in Helensburgh, from the first measured survey through planning and building control to the finished room.
- Guide price in HelensburghFrom £21,500 inc VAT
- PlanningScottish householder rules; building warrant needed
- Build time10–18 weeks on site
- Postcode districtsG84
Local to Helensburgh
Our survey diary covers Helensburgh, including G84. The same team covers Dunoon (8 miles), Oban (39 miles), all within easy reach.
For homes towards Renfrewshire and Inverclyde, Greenock is around 5 miles away. Scotland's housing includes sandstone villas, terraces and tenements in the cities and plenty of post-war and modern houses and bungalows elsewhere. A building warrant is needed before work starts.
What is included
- Structure, roof tied into the house
- Planning route checked or application made
- Foundations near boundaries and any drains
- New openings through the side wall
Planning and approvals in Helensburgh
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.
The planning position for a specific Helensburgh address depends on its history and any designations, which is why we check it at the first visit.
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.
Building close to a public sewer needs the agreement of Scottish Water, which we check during design.
Applications are decided by your council as planning authority.
Side extension prices in Helensburgh
These guide figures apply our Scotland adjustment (×0.98) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Helensburgh: £1,720 to £3,330 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2.5 m × 5 m 12 m² | £21,500 – £26,000 | £24,000 – £31,500 | £30,500 – £40,000 |
| 3 m × 6 m 18 m² | £30,500 – £37,500 | £36,000 – £47,000 | £45,500 – £60,000 |
| 3 m × 8 m 24 m² | £41,000 – £49,500 | £48,000 – £62,500 | £61,000 – £80,000 |
Try the guide-price tool to see a range for your own size and finish.
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
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Your questions about a side extension in Helensburgh
Who do I contract with for a side extension in Helensburgh?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Helensburgh, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Will my neighbours in Helensburgh 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 much does a side extension cost?
Our guide range is about £1,720 to £3,330 per m² including VAT, depending on specification, so a standard 18 m² single-storey side extension lands around £36,000 to £47,000 in Helensburgh.
Can I build over my driveway?
Yes, if the foundations work and you keep any parking the council requires. Drains and services under drives are common, so we check before design.
Book a free site visit in Helensburgh
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.