Two-storey wraparound extensions in Wealdstone

Before you start in Wealdstone, here's what applies.

Postcode districts: HA3
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: Harrow Weald (0.8 miles), Harrow (1.5 miles), Hatch End (1.7 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 Wealdstone we also work in Harrow Weald, Harrow and Hatch End, and across the rest of Greater London. Postcode district in and near Wealdstone: HA3.

What it costs in Wealdstone

Using our London rates, a two-storey wraparound extension 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, including VAT. Bigger or more glazed designs cost more per m². The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.

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 Wealdstone

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 Wealdstone homes

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.

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.

How we'd run your project

Free site visit
We visit your home in Wealdstone, look at the structure, access and boundaries, and talk through what you want the new rooms to do.
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.
Technical design
We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.
On site
One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.

Questions about two-storey wraparound extensions in Wealdstone

How much does a two-storey wraparound extension cost in Wealdstone?

Our guide for London, which covers Wealdstone, 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.

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.

Who handles building regulations for a project in Wealdstone?

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.

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.

Nearby

We also cover places near Wealdstone, including:

Other extensions in Wealdstone

All two-storey extension services in Wealdstone · Two-storey wraparound extensions across Greater London

Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Wealdstone.