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 Hammersmith?
In Hammersmith, 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. Prices across London are typically 30% above the UK average for this kind of work, which is reflected in the range for Hammersmith. 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 |
What moves the price most:
- Drainage changes
- Access for materials on terraced streets
- Steelwork and propping of the existing house
- Kitchen and flooring specification
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 Hammersmith?
The approval route for Hammersmith is set by planning law 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.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
Handled as part of most wraparound extensions:
- Underfloor heating option, electrics and plastering
- Structural engineer’s design for steels and supports
- Design and planning application
- Removal of internal and external walls
- Building control completion
- Walls, roof and glazing
How long does it take?
Allow 12 to 18 weeks on site. Design and approvals come first and typically take 3 to 4 months, depending on the approval route.
Building in Hammersmith
Space is at a premium in London, so homeowners often build out into the side return or up into the roof rather than move.
Projects in Hammersmith (W6 and W14) are surveyed in person before we quote, so the price reflects your actual property.
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
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 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 Hammersmith
Can we keep a separate living room?
Yes. Many clients keep the front room separate and open up only the back of the house.
Who approves a wraparound extension in Hammersmith?
Planning matters in Hammersmith go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
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 long does it take to build?
Around 12 to 18 weeks on site after approvals. Design, planning and party wall matters usually take 3 to 4 months beforehand.
How much does a wraparound extension cost in Hammersmith?
In Hammersmith, 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.