Rainham · Greater London

Two-storey wraparound extensions in Rainham

Want to stay in Rainham but need more space? A two-storey wraparound extension adds floor area on two levels without giving up much garden. Here's what's involved.

Useful details for planning a two-storey wraparound extension in Rainham.

Postcode districts
RM13
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
Elm Park (1.8 miles), Erith (2.5 miles), Belvedere (2.6 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.

Around Rainham we also work in Elm Park, Erith and Belvedere, and across the rest of Greater London. Postcode district in and near Rainham: RM13.

What it costs in Rainham

In London, which includes Rainham, we'd expect a two-storey wraparound extension to cost 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), or £2,580–£3,540 per m² including VAT. Professional fees for drawings and the structural engineer are listed separately on our prices page.

SpecPer m²An 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 Rainham

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 Rainham homes

Two roofs that meet

A wraparound needs the side roof and rear roof to join cleanly, often with a valley or hip where they meet. Getting pitches and ridge heights right keeps rainwater moving and avoids a bulky mass at the back corner, which neighbours and planners notice.

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.

How we'd run your project

  1. Look at the house

    We start in Rainham with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.

  2. Get it approved

    Once you're happy with the design we submit it to the council for Rainham and deal with any questions from the planning officer.

  3. Technical design

    We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.

  4. Finish and certify

    Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Questions about two-storey wraparound extensions in Rainham

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 Rainham?

Rainham 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.

Which postcodes do you cover around Rainham?

We cover Rainham (RM13) and nearby places including Elm Park, Erith and Belvedere, plus the rest of Greater London. The first site visit is free.

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.

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.

Nearby

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

Other extensions in Rainham

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

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

CallGuide price