Two-storey wraparound extensions in Rainhill

Rainhill: the key facts for this kind of project.

Postcode districts: L35
County / area: Merseyside, England
Price region: North West England
Guide price: £114,500–£157,000 (£2,040–£2,800 per m²)
Approval route: Planning permission is needed: the side part takes it outside permitted development in England.
Nearest towns: Whiston (1 mile), Prescot (1.7 miles), St Helens (2.7 miles)
Distance to Liverpool: about 8.7 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.

Around Rainhill we also work in Whiston, Prescot and St Helens, and across the rest of Merseyside. Postcode district in and near Rainhill: L35.

What it costs in Rainhill

Expect a two-storey wraparound extension in Rainhill to land somewhere around £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). Our North West England guide rate is £2,040–£2,800 per m², including VAT. Professional fees for drawings and the structural engineer are listed separately on our prices page.

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	£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

Planning and building regulations in Rainhill

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 Rainhill 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.

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

Visit and first ideas
One of our team visits your house in Rainhill, checks the walls, roof and drains, and sketches out options with you.
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.
Structure and building control
A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.
Build it
The new structure goes up first, then we open into the house, finish inside and get the completion certificate.

Questions about two-storey wraparound extensions in Rainhill

Who handles building regulations for a project in Rainhill?

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.

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

Rainhill 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 Rainhill?

We cover Rainhill (L35) and nearby places including Whiston, Prescot and St Helens, plus the rest of Merseyside. The first site visit is free.

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.

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.

Nearby

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

Other extensions in Rainhill

All two-storey extension services in Rainhill · Two-storey wraparound extensions across Merseyside

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