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.
Across North Yorkshire, people look into a single-storey extension to replace something worn out, to make the house work better for them, or to get it ready for a sale. We cover York, Middlesbrough, Harrogate and Scarborough and the smaller towns around them, working to the rules that apply in England. Expect a guide of £33,000–£70,000, VAT included, in Yorkshire and the Humber, and every quote follows a free visit.
- Guide price
- £33,000–£70,000 inc VAT
- Time on site
- 10–16 weeks on site
- Planning rules
- England
- Price level
- About 6% below the national guide
- Towns listed
- 8
- Survey
- Free, with a written quote
Single-storey extensions prices in North Yorkshire
The costs listed here are typical for a single-storey extension around North Yorkshire and include VAT. They reflect labour and material costs in Yorkshire and the Humber, about 6% below the national guide, giving a range of £33,000–£70,000. Exact pricing depends on your home, so we only fix it once a free site survey is done.
| Type of job | What it usually involves | Guide in North Yorkshire |
|---|---|---|
| Small extension (8–12m²) | A modest rear or side extension, such as a utility room or a slightly larger kitchen. | £20,500–£37,500 |
| Typical rear extension (15–25m²) | A kitchen-diner or family room with bifold doors and a rooflight or lantern. | £33,000–£70,000 |
| Large or wrap-around (30m² plus) | A wrap-around or wide rear extension, often with structural steelwork into the house. | £66,000–£122,000 |
What moves the price up or down:
- 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’s included?
- Cavity walls built and insulated to building regulations
- Flat or pitched roof, with rooflights or a lantern if specified
- Steel beams to open into the existing house
- Electrics and plumbing by qualified trades, with certificates
- Plastering, screed floor and internal doors
- Building control inspections and completion certificate
Housing across North Yorkshire
York has medieval timber-framed, Georgian and Victorian buildings, Harrogate has stone Victorian villas and terraces, and the Dales and Moors are built of limestone and sandstone, often under stone-slate or pantile roofs. Teesside towns within the county, such as Middlesbrough and Redcar, have Victorian red-brick terraces and post-war estates.
Dales and Moors properties often need lime pointing, roof repairs and window designs acceptable within a national park. Teesside brick terraces suit loft rooms and rear extensions, and estate homes commonly take garage conversions.
High ground in the Dales and Moors sees snow, frost and strong winds, while the coast faces cold North Sea weather.
Planning and building rules in North Yorkshire
North Yorkshire is in England, so the planning and building rules set out below are the ones that apply. We confirm the details with the council before we quote.
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.
How does the job run?
We look at the job
We begin by looking at the job in person. During the free survey we discuss options, materials and budget for a single-storey extension, and photograph or measure anything the quote needs to reflect.
Written quote
We put everything into a written, fixed-price quote: the specification, what's excluded, staged payments and the expected time on site. Take whatever time you need to decide; there's no pressure to commit.
Plan and prepare
With the quote agreed, we book the work in and handle preparation: permissions where needed, building control notifications, material orders and access arrangements for your North Yorkshire property.
The work itself
On site, the agreed plan is followed and any change is put in writing first. At completion we do a final clean, go through the snagging list with you and leave you with the relevant documents.
What you can expect from us
Frequently asked questions
Do I need planning permission for a single-storey extension?
Whether you need planning permission depends on the extension's size and height, how close it is to boundaries, your home's location, whether it is listed or in a conservation area, and which UK nation you live in. In England, many rear extensions up to 3m deep on a semi or terrace, or 4m on a detached house, can be built under permitted development. We check the rules that apply to your home before quoting.
How much does a single-storey extension cost?
A typical single-storey rear extension of 15–25m² costs £33,000–£70,000, 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.
What does a typical extension build look like week by week?
A typical single-storey extension follows the same order: clearing the site and digging foundations, building walls up to roof level, then fitting the roof and windows to make it weathertight. Electrics, plumbing, insulation and plastering follow. The last stage is opening into the house, laying the screed and fitting doors and finishes. Building control inspects at key stages, and we book those visits for you.
How much will a single-storey extension cost in North Yorkshire?
As a guide, expect to pay £33,000–£70,000 including VAT for a single-storey extension in North Yorkshire. That range is adjusted for Yorkshire and the Humber, which runs about 6% below the national guide. Where your project lands depends on size, materials, access and the condition of what is already there. We confirm a fixed price in writing after a free survey of your home.
Do I need planning permission in North Yorkshire?
It depends on the work, the size of the project, your property type and whether the building is listed or in a conservation area. North Yorkshire 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.
Towns in North Yorkshire
Find your town below. Every place listed in North Yorkshire is covered for a single-storey extension, with the same survey, written quote and fixed-price process.

