A double-storey extension adds two floors of new space to your house in one build, typically a larger kitchen or living room downstairs with an extra bedroom, bathroom or en-suite above, sharing one set of foundations and one roof.
In Falkirk, as anywhere in Stirling, Falkirk and Clackmannanshire, the price of a double-storey extension is driven mainly by size, materials and access. Across Scotland our guide sits at £58,000–£115,000 with VAT, but restricted parking, a narrow side passage or extra preparation can move the figure either way. That is why every price we give follows a visit to the house.
- Guide price
- £58,000–£115,000 inc VAT
- Time on site
- 14–22 weeks on site
- Postcodes
- FK1, FK2 and FK5
- Planning rules
- Scotland
- Local area
- Stirling, Falkirk and Clackmannanshire
- Survey
- Free, with a written quote
Double-storey extensions prices in Falkirk
Here is how the guide price for a double-storey extension breaks down in Falkirk. We start from national figures and adjust for Scotland, which comes out about 4% below the national guide. The resulting range, VAT included, is £58,000–£115,000, and a survey, at no cost to you, firms it up.
| Type of job | What it usually involves | Guide in Falkirk |
|---|---|---|
| Small (15–20m² total) | A compact rear or side extension adding a small room on each floor. | £38,500–£62,000 |
| Typical (30–40m² total) | A larger kitchen or living room below with a double bedroom or en-suite above. | £58,000–£115,000 |
| Large (50m² plus total) | Wide or deep extensions, often with a new bathroom, steelwork and high-spec glazing. | £96,000–£173,000 |
Your price depends mostly on:
- Combined floor area across both storeys
- How the new roof joins the existing roof
- Foundation depth, ground conditions and drains to divert
- Scaffolding duration, access and the level of finishes
Scope of the work
- Groundworks, foundations and below-ground drainage
- Insulated cavity walls with brick or render to match the house
- First-floor joists, stud walls and new openings upstairs
- Electrics, plumbing and heating by qualified trades, with certificates
- Windows, external doors, plastering and internal doors
- Building control inspections and completion certificate
What are homes like around Falkirk?
Stirling's old town has historic stone buildings, with Victorian villas in the King's Park area and newer estates around the city. Falkirk and Grangemouth have industrial-era terraces and post-war housing, and Alloa and the Hillfoots villages in Clackmannanshire mix stone cottages, mill-era housing and harled council homes.
Stone homes commonly need repointing and slate roof repairs, and harled houses need re-rendering. Semis and bungalows suit extensions and loft conversions, and newer homes take garage conversions and driveways.
Whatever era your Falkirk home dates from, we plan a double-storey extension around how it is actually built rather than a one-size-fits-all specification.
Permissions for a double-storey extension in Falkirk
Homes in Falkirk come under the regulations for Scotland, summarised below. We don't rely on general rules alone: we confirm the position for your address with the council before a quote goes out.
In Scotland, extensions of more than one storey are only permitted development in narrow cases (Class 1B, well away from the boundary they face and outside conservation areas), so most need planning permission.
A building warrant is required before work starts. Scotland has no Party Wall Act; neighbour and title issues are handled under general law.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
How does the job run?
A visit to your home
Book a visit and we'll come to you. The survey covers measurements, the state of what's there now and any obvious constraints, so the price that follows is based on your actual home, not an average.
Written quote
The quote arrives in writing, not over the phone. It covers the full scope, the finishes you've chosen, any exclusions and the payment schedule, with a fixed price tied to that specification.
Dates and permissions
Once you accept, we agree start dates, order materials and deal with any planning, building control or neighbour notices the job needs. You'll know who is coming and when before work begins.
On site to finish
The job proceeds in the order set out in the programme, with dust and debris kept under control. Finally we tidy away, inspect the work together and pass the finished project over to you with its paperwork.
How we work
Frequently asked questions
Can we live at home while it is built?
Most families stay at home during a double-storey extension. The new structure is built outside first, and we only break through into the existing rooms near the end, usually one floor at a time. Upstairs, this may mean a bedroom is out of use for a week or two. We fit dust screens, protect floors and stairs, and plan any time without water or power in advance.
How long does a double-storey extension take?
A double-storey extension typically takes 14–22 weeks on site, depending on size, roof design and weather. Foundations and ground-floor walls come first, then the first-floor joists, upper walls and roof. Once it is weathertight, electrics, plumbing, plastering and finishes follow. Allow extra time beforehand for drawings, calculations and approvals. We give you a stage-by-stage programme with your quote.
Is a double-storey extension better value than single-storey?
A double-storey extension usually gives better value per square metre than a single-storey one, because the same foundations and roof serve twice the floor area. The overall cost is higher, and planning can be harder because of the effect on neighbours. If you might want an extra bedroom later, building both floors now avoids a second round of disruption and scaffolding.
What happens at the survey?
We visit your home at a time that suits you, look at the area involved, take measurements and check access, condition and any services that might be affected. We talk through what you want from a double-storey extension, explain the options and answer questions. There is no charge and no obligation; afterwards we send a written quote.
Can you combine a double-storey extension with other work?
Yes. Because we manage several trades under one contract, we can plan a double-storey extension alongside other work on your Falkirk home, such as new windows with rendering, or a kitchen refit with an extension. Combining jobs can reduce repeat set-up such as scaffolding, skips and access, and every element is listed and priced in the same written quote.
Also covering areas around Falkirk
We survey and quote throughout Falkirk's FK1, FK2 and FK5 postcodes and in surrounding places such as Grangemouth, Alloa and Cumbernauld. The process and pricing approach are identical in each of them.

