What is a wraparound extension?
A wraparound extension combines a side return and a rear extension into one L-shaped addition. It gives the largest possible ground floor, often creating an open-plan kitchen, dining and living space across the whole width of the house.
How much does a wraparound extension cost in Dumbarton?
In Dumbarton, a wraparound extension typically costs £2,150–£3,100 per m² of floor area, including VAT at 20% (standard rate). For a typical 28 m² project that is roughly £60,000–£87,000. Prices in Scotland sit near the national average for this kind of work, and the range for Dumbarton reflects that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (20 m²) | £43,000–£62,000 |
| Typical project (28 m²) | £60,000–£87,000 |
| Larger project (39 m²) | £84,000–£121,000 |
| Rate per m² | £2,150–£3,100 |
The main things that change the cost:
- Agreements with neighbours on shared walls
- Total footprint and the amount of glazing
- Access for materials on terraced streets
- Steelwork and propping of the existing house
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 wraparound extension in Dumbarton?
The approval route for Dumbarton is set by planning law in Scotland. In Scotland a wraparound extension normally needs planning permission and a building warrant.
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.
We check this for your address before design work starts, so there are no surprises later.
What we handle
On a typical wraparound extension we handle:
- Structural engineer’s design for steels and supports
- Removal of internal and external walls
- Walls, roof and glazing
- Foundations and drainage
- Written agreement with neighbours on shared walls
- Building control completion
How long does it take?
Expect 12 to 18 weeks on site. Before that, surveys, drawings and approvals usually take 3 to 4 months, longer if the council asks for changes.
Building in Dumbarton
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.
We work across Dumbarton and neighbouring areas such as Erskine, Clydebank and Greenock. Postcodes we cover in Dumbarton include G82.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 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 wraparound extensions in Dumbarton
How long does a wraparound extension take in Dumbarton?
Typically 12 to 18 weeks on site. Design and approvals beforehand usually take 3 to 4 months.
Do I need planning permission for a wraparound extension in Dumbarton?
In Scotland a wraparound extension normally needs planning permission and a building warrant.
What about the old back addition?
The side wall of the back addition is usually removed and replaced with a steel beam, so the old kitchen joins the new space.
Can we keep a separate living room?
Yes. Many clients keep the front room separate and open up only the back of the house.
Is a wraparound worth it?
It gives the biggest ground-floor space without going upwards. Whether it adds value depends on your street and house, so we suggest checking local sale prices before committing.
How much does a wraparound extension cost in Dumbarton?
In Dumbarton, a wraparound extension typically costs £2,150–£3,100 per m² of floor area, including VAT at 20% (standard rate). A typical 28 m² project comes to roughly £60,000–£87,000. Your fixed price depends on the survey and drawings.