Lancashire · England

Two-storey wraparound extensions in Lancashire

Lancashire has a wide mix of house types, and most can take a well-designed two-storey wraparound extension. Here's what's involved, the rules in England and typical costs.

Lancashire at a glance

Nation
England
Price region
North West England
Postcode areas
BB, FY, L, LA, OL, PR, WN
Towns covered
30 listed below, plus surrounding villages
Approval route
Planning permission is needed: the side part takes it outside permitted development in England.
Site visits
Free, no obligation

What a two-storey wraparound extension involves

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.

Lancashire towns we list: Preston (PR1), Burnley (BB10), Blackburn (BB1), Blackpool (FY1), Morecambe (LA4) and Lancaster (LA1). Every other address in Lancashire is covered as well.

Guide price in North West England

Guide prices for two-storey wraparound extensions in North West England are around £2,040–£2,800 per m² of new floor space, including VAT. For 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), that's roughly £114,500–£157,000. Keep a contingency of around 10% for things nobody can see until the ground is opened up.

SpecPer m²Typical project
Essential£1,880–£2,580 per m²£105,000–£144,500
Standard£2,040–£2,800 per m²£114,500–£157,000
Premium£2,450–£3,360 per m²£137,500–£188,500

Rules in England

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.

The Party Wall etc. Act 1996 applies, so notices may be needed for work on or near a shared wall or boundary.

Getting the design right

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 work in Lancashire

  1. Understand the brief

    At your home in Lancashire we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.

  2. Get it approved

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

  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.

Towns we cover in Lancashire

Two-storey wraparound extensions in Lancashire: questions

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

In North West England our guide is £2,040–£2,800 per m² including VAT, so about £114,500–£157,000 for an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space). Essential and Premium specs move that by roughly 8% down or 20% up.

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.

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.

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.

Will I need planning permission in Lancashire?

Lancashire is in England. Planning permission is needed: the side part takes it outside permitted development in England.

Neighbouring areas

All extension services in Lancashire · About two-storey wraparound extensions

Ready to see what a second storey could do for your home?

Book a free site visit. We'll look at your house, talk through options and explain the approvals you'd need, then price the design stage in writing.

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