Aylesbury · Buckinghamshire

Two-storey wraparound extensions in Aylesbury

Thinking about a two-storey wraparound extension in Aylesbury? We design it, take it through the approvals it needs and build it, with one team responsible from the first visit to the final certificate.

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

Postcode districts
HP17, HP19, HP20, HP21 and HP22
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
Tring (6.9 miles), Thame (8.4 miles), Leighton Buzzard (9.6 miles)
Distance to Milton Keynes
about 15.7 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 Aylesbury (HP17, HP19, HP20, HP21 and HP22) and the places around it, including Tring (6.9 miles), Thame (8.4 miles) and Leighton Buzzard.

What it costs in Aylesbury

Expect a two-storey wraparound extension in Aylesbury to land somewhere around £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). Our South East England guide rate is £2,360–£3,250 per m², including VAT. We'll give you a written design-stage price first, then a fixed build price once the drawings are agreed.

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 Aylesbury

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 Aylesbury 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. Start at your house

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

  2. 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.

  3. Fixed price in writing

    With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.

  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 Aylesbury

Who handles building regulations for a project in Aylesbury?

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.

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

Our guide for South East England, which covers Aylesbury, is £2,360–£3,250 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 £132,500–£181,500. 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.

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.

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

Other towns near Aylesbury:

Other extensions in Aylesbury

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

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

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