Two-storey wraparound extensions in Seven Sisters
Adding a two-storey wraparound extension in Seven Sisters 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.
Before you start in Seven Sisters, here's what applies.
- Postcode districts
- N15
- 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
- Stamford Hill (0.7 miles), Harringay (0.9 miles), Stroud Green (1.4 miles)
- First visit
- Free, no obligation
About a two-storey wraparound extension
A two-storey wraparound extension suits a house with space both beside it and behind it, where you want to transform the layout rather than add a single room. You get one design for the whole L-shape, the planning application, structural design for the corner and the openings into the house, building regulations approval and the build, managed by us and carried out by vetted teams working under S&K.
We cover Seven Sisters (N15) and the places around it, including Stamford Hill (0.7 miles), Harringay (0.9 miles) and Stroud Green.
What it costs in Seven Sisters
Expect a two-storey wraparound extension in Seven Sisters to land somewhere around £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). Our London guide rate is £2,580–£3,540 per m², including VAT. Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.
| 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 Seven Sisters
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 Seven Sisters homes
The corner post
At the outside corner of the L, there is no existing wall to carry the floor above. Opening the ground floor fully usually means a steel frame or a corner post, and the engineer's design sets how slim it can be. We decide early whether you want a clear corner or a visible post.
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
Understand the brief
At your home in Seven Sisters we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.
Design and approvals
We draw the extension and check it against the rules for England, then apply for planning permission or a certificate of lawfulness, whichever fits.
Fixed price in writing
With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.
Build and sign-off
Vetted teams working under S&K build the extension, and we arrange the building control completion certificate at the end.
Questions about two-storey wraparound extensions in Seven Sisters
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 Seven Sisters?
Our guide for London, which covers Seven Sisters, 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.
Who handles building regulations for a project in Seven Sisters?
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.
Can a wraparound extension be part single, part two-storey?
Yes. Many wraparounds keep the rear part single storey with roof lights over the kitchen and put the two-storey part to the side. This can reduce the effect on neighbours and the cost. We set out both options at the design stage, so you can compare floor space against price before choosing.
Is a wraparound extension better than separate side and rear extensions?
Building both at once usually costs less than two separate projects, because you pay for one set-up, one scaffold, one roof junction and one set of approvals. It also lets the layout be designed as a whole. The trade-off is a larger single outlay and a longer build, often 16 to 24 weeks at this size.
Nearby
We also cover places near Seven Sisters, including:
Other extensions in Seven Sisters
- 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 Seven Sisters · Two-storey wraparound extensions across Greater London
The quickest next step is a visit. We'll look at your house in Seven Sisters and give you an honest view of the options.