Two-storey wraparound extensions in Purley

The basics for Purley at a glance.

Postcode districts: CR8
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: Kenley (0.9 miles), Sanderstead (1.5 miles), Coulsdon (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.

We cover Purley (CR8) and the places around it, including Kenley (0.9 miles), Sanderstead (1.5 miles) and Coulsdon.

What it costs in Purley

Expect a two-storey wraparound extension in Purley 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 Purley

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 Purley 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

Visit and first ideas
One of our team visits your house in Purley, checks the walls, roof and drains, and sketches out options with you.
Drawings and permission
Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Purley.
Engineer it
Foundations sized for two floors, steels for any openings, and building control approval, all before anyone starts on site.
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 Purley

Which postcodes do you cover around Purley?

We cover Purley (CR8) and nearby places including Kenley, Sanderstead and Coulsdon, plus the rest of Greater London. The first site visit is free.

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.

Do I need planning permission for a two-storey wraparound extension in Purley?

Purley is in England, so England planning rules apply. Planning permission is needed: the side part takes it outside permitted development in England. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

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.

Does a wraparound extension need steel?

Almost always. Opening the corner of the house and the old rear wall to make one open-plan space means steel beams, and often a steel post or frame at the outside corner. The structural engineer sizes these, and the steel is ordered once the design is fixed, which is one reason a wraparound needs careful sequencing.

Nearby

Close to Purley? We work across the area, including:

Other extensions in Purley

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

Tell us about your house in Purley and we'll call you back to arrange a free, no-obligation visit.