Thurso flat roof extensions, designed and built
We take on flat roof extensions in Thurso by arrangement. Because of travel and logistics, we agree the programme and any travel costs in writing before the survey.
- Guide price in ThursoFrom £20,500 inc VAT
- PlanningScottish householder rules; building warrant needed
- Build time10–16 weeks on site
- Postcode districtsKW14
Local to Thurso
Across KW14, we can visit, measure and advise. Island and remote projects are planned individually, with travel, deliveries and accommodation for the team agreed before the survey.
Across Scotland, extensions follow Scottish planning and building standards, including the building warrant process, which we build into the programme from the start.
What we take care of
- Membrane choice: single-ply, EPDM or GRP
- Warm-roof design with insulation above the deck
- Parapets or edge trims and flashings to the house
- Lanterns or rooflights with upstands
- Falls and outlets designed to drain properly
Height is often what decides a flat roof. Under first-floor windows, a pitched roof may not fit at all; a flat roof keeps the extension low while still giving a good ceiling height inside.
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. Separately, almost every extension needs a building warrant from the council before work starts.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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.
How much does a flat roof extension cost in Thurso?
Prices below are for Thurso, using the Scotland factor of ×0.98. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Thurso: £1,720 to £3,280 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m 12 m² | £20,500 – £24,500 | £24,000 – £31,000 | £30,500 – £39,500 |
| 4 m × 5 m 20 m² | £34,000 – £40,500 | £40,000 – £51,000 | £50,500 – £66,000 |
| 5 m × 6 m 30 m² | £51,000 – £60,500 | £60,000 – £76,500 | £76,000 – £98,500 |
Try the guide-price tool to see a range for your own size and finish.
How the project works
Visits to Thurso are arranged around travel; we confirm any travel costs in writing before the survey.
Site visit by arrangement
We visit your Thurso home, measure up, talk through what you want and check the planning position.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Questions people ask about flat roof extensions
Do you cover all of Thurso?
Yes. We cover Thurso and the surrounding parts of Highlands and Islands. Projects here are taken on by arrangement because of travel, and any travel costs are agreed before the survey.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Thurso, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do I need building regulations approval in Thurso?
Yes. Almost every extension needs it, whatever the planning route. In Scotland that means a building warrant before work starts.
Are flat roof extensions cheaper?
Usually slightly, because there is less roof structure and no tiles. Our guide range is about £1,720 to £3,280 per m² including VAT.
Can I walk on a flat roof extension?
Only for maintenance unless it is designed as a terrace. A roof terrace or balcony needs planning permission and a different structure.
Talk to us about a project in Thurso
We will talk through the project, the planning position and how we would organise the visit and the build.
- Site visit arranged around travel, costs agreed first
- 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 .
Send us your project details
Tell us a little about the project and we will arrange a time.