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 Lewisham?
In Lewisham, a wraparound extension typically costs £2,850–£4,150 per m² of floor area, including VAT at 20% (standard rate). For a typical 28 m² project that is roughly £80,000–£116,000. The guide for Lewisham reflects typical costs in London, roughly 30% above the UK-wide figure. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| Smaller project (20 m²) | £57,000–£83,000 |
| Typical project (28 m²) | £80,000–£116,000 |
| Larger project (39 m²) | £111,000–£162,000 |
| Rate per m² | £2,850–£4,150 |
The main things that change the cost:
- Party wall surveyor fees for one or both neighbours
- Total footprint and the amount of glazing
- Access for materials on terraced streets
- Kitchen and flooring specification
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 Lewisham?
Before anything is built in Lewisham, we confirm which approvals apply 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.
We check this for your address before design work starts, so there are no surprises later.
What we handle
Handled as part of most wraparound extensions:
- Removal of internal and external walls
- Building control completion
- Party wall notices and surveyor liaison
- Structural engineer’s design for steels and supports
- Design and planning application
- Walls, roof and glazing
How long does it take?
The build itself usually takes 12 to 18 weeks on site. Allow time beforehand for drawings and approvals, usually 3 to 4 months.
Building in Lewisham
Space is at a premium in London, so homeowners often build out into the side return or up into the roof rather than move.
We work across Lewisham and neighbouring areas such as Forest Hill, Catford and Peckham. Postcodes we cover in Lewisham include SE13 and SE22.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 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
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about wraparound extensions in Lewisham
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 Lewisham?
In Lewisham, a wraparound extension typically costs £2,850–£4,150 per m² of floor area, including VAT at 20% (standard rate). A typical 28 m² project comes to roughly £80,000–£116,000. Your fixed price depends on the survey and drawings.
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.
Who approves a wraparound extension in Lewisham?
Planning matters in Lewisham go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.