A single-storey extension is a new ground-floor room built onto your house, usually at the rear or side, with its own foundations, walls and roof, creating a bigger kitchen, living space or bedroom without moving home.
Addresses across WA3 and WA12 fall within our coverage for a single-storey extension, so if your home is in Newton-le-Willows we can arrange a survey on a day that works for you. We inspect the existing building, discuss materials and layout, and then price the agreed specification in writing. Expect a guide range of £33,000–£71,000 including VAT before that visit.
- Guide price
- £33,000–£71,000 inc VAT
- Time on site
- 10–16 weeks on site
- Postcodes
- WA3 and WA12
- Planning rules
- England
- Local area
- St Helens
- Survey
- Free, with a written quote
Single-storey extensions prices in Newton-le-Willows
These are guide costs, not quotes. For a single-storey extension in Newton-le-Willows the range is £33,000–£71,000, VAT included, reflecting prices in the North West that are about 5% below the national guide. Once we have visited for a free survey, you get a firm figure for the scope you approve.
| Type of job | What it usually involves | Guide in Newton-le-Willows |
|---|---|---|
| Small extension (8–12m²) | A modest rear or side extension, such as a utility room or a slightly larger kitchen. | £21,000–£38,000 |
| Typical rear extension (15–25m²) | A kitchen-diner or family room with bifold doors and a rooflight or lantern. | £33,000–£71,000 |
| Large or wrap-around (30m² plus) | A wrap-around or wide rear extension, often with structural steelwork into the house. | £66,000–£124,000 |
Your price depends mostly on:
- Floor area, shape and number of corners
- Roof type, rooflights, lanterns and the amount of glazing
- Steelwork needed to open into the existing house
- Finishes, kitchen, flooring and heating specification
What do you get?
- Cavity walls built and insulated to building regulations
- Steel beams to open into the existing house
- Electrics and plumbing by qualified trades, with certificates
- Windows and external doors, including bifolds if chosen
- Plastering, screed floor and internal doors
- Building control inspections and completion certificate
Homes in Merseyside
Liverpool's housing includes Georgian terraces near the centre, large areas of Victorian red-brick terraces, Edwardian semis in the suburbs and big interwar council estates. The Wirral has Victorian villas and interwar semis, Southport has Victorian villas and bungalows, and St Helens and Knowsley have post-war estates and newer housing.
Terraces suit loft rooms, kitchen extensions and repointing, and many need their roofs and windows renewed. Suburban semis commonly take side extensions, driveways and porches.
In Newton-le-Willows, as elsewhere in Merseyside, we take the building's age and construction into account before recommending anything, because both can change what is involved in a single-storey extension.
Do you need permission in Newton-le-Willows?
For anyone in Newton-le-Willows, the relevant framework is England's. The summary below is general, so we always contact the council about your address before putting a price in writing.
In England, many single-storey rear extensions are permitted development: typically up to 3 m deep on a semi-detached or terraced house and 4 m on a detached house, no more than 4 m high, and covering no more than half the land around the original house. Larger rear extensions can go through the prior approval process. Side extensions, flats, listed buildings, conservation areas and homes where permitted development rights have been removed need planning permission.
Building Regulations approval is needed for almost every extension, covering foundations, structure, insulation, drainage, ventilation and fire safety. If the work is on or near a shared wall or boundary, the Party Wall etc. Act 1996 may apply.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
From survey to handover
A visit to your home
First, someone visits your home in Newton-le-Willows to see the space, take measurements and note anything that could affect the work, such as access or the condition of what is there. There is no charge for this visit.
Quote in writing
We turn the survey notes into a written quote. The price is fixed for the specification we agree, and the document sets out materials, scope and payment stages in plain language.
Getting ready
Preparation matters as much as the build. We agree access, parking and working hours with you, order materials in good time, and confirm any permissions so the job isn't held up once it starts.
Build and hand over
Our trades complete a single-storey extension while your point of contact keeps you updated. When everything is finished, we clear the site, take away waste and go through the result with you before handover.
Working with SK Home Improvements
Single-storey extensions in Newton-le-Willows: questions
What happens at the survey?
We visit your home at a time that suits you, look at the area involved, take measurements and check access, condition and any services that might be affected. We talk through what you want from a single-storey extension, explain the options and answer questions. There is no charge and no obligation; afterwards we send a written quote.
What is the Party Wall Act and does it apply to me?
The Party Wall etc. Act 1996 applies in England and Wales only. In England and Wales, it requires you to give notice to neighbours before certain work on or near a shared wall, such as digging foundations within 3m of their building and deeper than its footings. Neighbours can agree or appoint a surveyor. Scotland and Northern Ireland have no equivalent Act, though general rights still apply. We identify whether notices are needed during the survey.
Do I need planning permission in Newton-le-Willows?
It depends on the work, the size of the project, your property type and whether the building is listed or in a conservation area. Newton-le-Willows is in England, so England's rules apply. Many smaller jobs need no planning application, but some still need building control approval. We check what applies to your address before quoting.
How much does a single-storey extension cost?
A typical single-storey rear extension of 15–25m² costs £33,000–£71,000, built to a plastered finish ready for your kitchen and decoration. As a guide, allow roughly £1,600–£2,800 per square metre plus fixed costs for groundworks, steelwork and fees. Smaller extensions cost more per square metre. The kitchen, flooring and large glazed doors are usually the biggest extras. We confirm a fixed price for the agreed specification after the survey.
Is a flat roof or a pitched roof better on an extension?
A flat roof is quicker to build and usually costs less, gives a clean modern look and works well with a roof lantern. A pitched roof matches the main house, sheds water faster and allows a vaulted ceiling, but it costs more and its height can affect neighbours. Modern flat roofs in EPDM rubber or GRP last well when properly detailed. Planning rules on height can also decide the choice.
Nearby towns
We cover every part of Newton-le-Willows, including WA3 and WA12, and nearby Golborne, Ashton in Makerfield and Warrington. Wherever you are within that patch, the survey is free and the quote comes to you in writing.

