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 Darwen?
In Darwen, a wraparound extension typically costs £2,050–£3,000 per m² of floor area, including VAT at 20% (standard rate). For a typical 28 m² project that is roughly £57,500–£84,000. We start from a UK-wide guide and adjust it for the North West, where labour and materials are typically about 6% below average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (20 m²) | £41,000–£60,000 |
| Typical project (28 m²) | £57,500–£84,000 |
| Larger project (39 m²) | £80,000–£117,000 |
| Rate per m² | £2,050–£3,000 |
Your quote will depend mainly on:
- Access for materials on terraced streets
- Total footprint and the amount of glazing
- Steelwork and propping of the existing house
- Party wall surveyor fees for one or both neighbours
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for a wraparound extension in Darwen?
Whether you need planning permission depends on your house and its location in England. In England a wraparound extension combines side and rear elements, which normally takes it outside permitted development, so a householder planning application is made.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
From survey to sign-off, the job normally involves:
- Design and planning application
- Structural engineer’s design for steels and supports
- Removal of internal and external walls
- Party wall notices and surveyor liaison
- Walls, roof and glazing
- Foundations and drainage
How long does it take?
Build time is typically 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 Darwen
Terraced streets across the North West often suit rear dormers and single-storey kitchen extensions.
Our Darwen coverage includes postcode districts BB3, and we also work in nearby places such as Blackburn, Accrington and Chorley.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about wraparound extensions in Darwen
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.
How long does a wraparound extension take in Darwen?
Typically 12 to 18 weeks on site. Design and approvals beforehand usually take 3 to 4 months.
How much does a wraparound extension cost in Darwen?
In Darwen, a wraparound extension typically costs £2,050–£3,000 per m² of floor area, including VAT at 20% (standard rate). A typical 28 m² project comes to roughly £57,500–£84,000. Your fixed price depends on the survey and drawings.
Can we keep a separate living room?
Yes. Many clients keep the front room separate and open up only the back of the house.
Does a wraparound extension need planning permission?
Almost always. Combining side and rear elements usually goes beyond permitted development limits, so a householder planning application is normally made.