Beaconsfield · Buckinghamshire

Two-storey wraparound extensions in Beaconsfield

For a two-storey wraparound extension in Beaconsfield, the first questions are always the same: how big, which approvals, and what it will cost. This page answers all three for Buckinghamshire.

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

Postcode districts
HP9 and HP10
County / area
Buckinghamshire, England
Price region
South East England
Guide price
£132,500–£181,500 (£2,360–£3,250 per m²)
Approval route
Planning permission is needed: the side part takes it outside permitted development in England.
Nearest towns
Chalfont Saint Peter (3.9 miles), Amersham (4 miles), Gerrards Cross (4.3 miles)
Distance to Milton Keynes
about 30 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 Beaconsfield we also work in Chalfont Saint Peter, Amersham and Gerrards Cross, and across the rest of Buckinghamshire. Postcode districts in and near Beaconsfield: HP9 and HP10.

What it costs in Beaconsfield

Most of the cost of a two-storey wraparound extension is set by its size and specification. For Beaconsfield and the rest of South East England, our guide is £2,360–£3,250 per m² including VAT, so about £132,500–£181,500 for an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space). Keep a contingency of around 10% for things nobody can see until the ground is opened up.

SpecPer m²An L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space)
Essential£2,180–£2,990 per m²£122,000–£167,000
Standard£2,360–£3,250 per m²£132,500–£181,500
Premium£2,840–£3,890 per m²£159,000–£218,000

Planning and building regulations in Beaconsfield

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 Beaconsfield 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

  1. Start at your house

    We come to your home in Beaconsfield, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.

  2. Get it approved

    Once you're happy with the design we submit it to the council for Beaconsfield 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. 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 Beaconsfield

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

Beaconsfield 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 Beaconsfield?

We cover Beaconsfield (HP9 and HP10) and nearby places including Chalfont Saint Peter, Amersham and Gerrards Cross, plus the rest of Buckinghamshire. 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.

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

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

Other extensions in Beaconsfield

All two-storey extension services in Beaconsfield · Two-storey wraparound extensions across Buckinghamshire

Book a free site visit in Beaconsfield and we'll tell you what's possible, what approvals you need and what the design stage would cost.

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