Two-storey wraparound extensions in Hampstead
Adding a two-storey wraparound extension in Hampstead gives you two new rooms stacked on one footprint. Here's how we'd approach it, what it typically costs and the rules that apply in England.
What we'd confirm first for a project in Hampstead.
- Postcode districts
- NW3
- County / area
- Greater London, England
- Price region
- London
- Guide price
- £144,500–£198,000 (£2,580–£3,540 per m²)
- Approval route
- Planning permission is needed: the side part takes it outside permitted development in England.
- Nearest towns
- Belsize Park (0.6 miles), Kilburn (0.6 miles), Highgate (1.1 miles)
- First visit
- Free, no obligation
About a two-storey wraparound extension
A two-storey wraparound extension is an L-shaped addition that extends both the side and the rear of your house, on two floors. It gives one of the largest gains in floor space of any extension, typically a big open-plan kitchen and living area below and two or more bedrooms or bathrooms above. In England it needs planning permission, because the side part is more than one storey.
Around Hampstead we also work in Belsize Park, Kilburn and Highgate, and across the rest of Greater London. Postcode district in and near Hampstead: NW3.
What it costs in Hampstead
Most of the cost of a two-storey wraparound extension is set by its size and specification. For Hampstead and the rest of London, our guide is £2,580–£3,540 per m² including VAT, so about £144,500–£198,000 for an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space). These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.
| Spec | Per m² | An L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space) |
|---|---|---|
| Essential | £2,370–£3,260 per m² | £133,000–£182,500 |
| Standard | £2,580–£3,540 per m² | £144,500–£198,000 |
| Premium | £3,100–£4,250 per m² | £173,500–£238,000 |
Planning and building regulations in Hampstead
In England, a two-storey wraparound extension needs householder planning permission, because any extension beyond a side wall must be single storey to be permitted development. The application costs £548 (or £575 for applications made from 8 December 2026). Councils weigh the side part against the street scene and the rear part against neighbours' light and outlook, and should decide within 8 weeks of validation.
Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.
Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.
Design points for Hampstead homes
Phasing the build
A wraparound touches two sides of the house at once, so the kitchen and often the rear rooms are out of use for part of the build. We plan the sequence so you keep a working kitchen and bathroom for as long as possible, or advise when moving out briefly makes sense.
Daylight to the middle
A deep L-shaped plan can leave the middle of the ground floor dark, because the old rear rooms are now enclosed. We use wide rear openings, a well-placed stair and, where part of the extension is single storey, roof lights, while keeping total glazing within the Part L allowance.
How we'd run your project
Look at the house
We start in Hampstead with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
Technical design
We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.
Build and hand over
We manage the build from groundworks to decoration-ready finish and hand over with the completion paperwork.
Questions about two-storey wraparound extensions in Hampstead
Who handles building regulations for a project in Hampstead?
We handle it as part of the project. What's needed in England: building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.
How long does a two-storey wraparound extension take?
Allow 4 to 8 weeks for survey and design, then the approval period (councils should decide householder applications within 8 weeks of validation), then 4 to 8 weeks of technical design, which can overlap. The build itself usually takes 14 to 20 weeks, longer for large or complex designs.
How much does a two-storey wraparound extension cost in Hampstead?
Our guide for London, which covers Hampstead, is £2,580–£3,540 per m² including VAT. A typical project with an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space) comes to about £144,500–£198,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.
Can I stay at home during a wraparound extension?
Many people do, but a wraparound affects two sides of the house and usually the kitchen, so there will be weeks without a full kitchen. We plan a temporary kitchen, keep a route through the house and seal off the work area. For some families, moving out while the rear wall is opened up is easier.
How much floor space does a wraparound extension add?
It depends on the width of the side plot and the depth at the rear. Our guide prices are based on a typical wraparound with an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space). Yours may be larger or smaller, and the measured survey shows what your plot can take.
Nearby
Close to Hampstead? We work across the area, including:
Other extensions in Hampstead
- Rear
- Side
- Part two-storey
- Over a garage
- First floor
- Semi-detached
- Detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Hampstead · Two-storey wraparound extensions across Greater London
Book a free site visit in Hampstead and we'll tell you what's possible, what approvals you need and what the design stage would cost.