Annexe extensions in Grangemouth
A annexe extension in Grangemouth starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in GrangemouthFrom £53,500 inc VAT
- PlanningScottish householder rules; building warrant needed
- Build time16–24 weeks on site
- Postcode districtsFK2, FK3

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.
In a conservation area or national scenic area the householder permitted development rights are more limited, listed homes need listed building consent, and if rights have been removed by a condition or direction, any extension needs an application.
Building close to a public sewer needs the agreement of Scottish Water, which we check during design.
In Scotland a building warrant from the council is needed before work starts on almost any extension, and a completion certificate is issued when the work is accepted. Building standards are set in the Scottish technical handbooks.
Applications are decided by your council as planning authority.
Local to Grangemouth
Our survey diary covers Grangemouth, including FK2, FK3. The same team covers Falkirk (3 miles), Alloa (8 miles), Stirling (11 miles), all within easy reach.
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.
Who an annexe extension suits
- Multi-generational families
- Relatives who need support close by
- Homes with a large side or rear garden
How much does an annexe extension cost in Grangemouth?
Prices below are for Grangemouth, using the Scotland factor of ×0.98. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Grangemouth: £1,960 to £3,720 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Studio annexe 25 m² | £53,500 – £67,500 | £58,500 – £73,500 | £73,500 – £93,500 |
| One-bedroom annexe 35 m² | £68,500 – £86,000 | £82,000 – £103,000 | £102,500 – £130,500 |
| Larger annexe 45 m² | £88,000 – £110,500 | £105,500 – £132,500 | £132,000 – £168,000 |
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
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
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
The build is managed from start to finish, inspected at each stage and signed off on completion.
Common questions in Grangemouth
Do I need building regulations approval in Grangemouth?
Yes. Almost every extension needs it, whatever the planning route. In Scotland that means a building warrant before work starts.
How long does an annexe extension take to build in Grangemouth?
On site, typically 16 to 24 weeks once approvals are in place. Before that, allow 10–16 weeks design and approvals.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Grangemouth, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Can the annexe have its own front door?
Yes, many do, but it should still connect to the main house to stay clearly part of it.
Does an annexe extension need planning permission?
Usually yes, because of its size and the way it will be used. Councils check that it stays ancillary to the main house, so the application must describe the use clearly.
Book a free site visit in Grangemouth
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.