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.
Homes across West Yorkshire vary a great deal, so we price a single-storey extension only after seeing the property. Our coverage takes in Leeds, Bradford, Huddersfield and Wakefield and the surrounding districts. As a guide, expect £33,000–£70,000 including VAT in Yorkshire and the Humber; the final figure depends on size, materials and access. Any permissions are checked against the rules for England before we quote.
- 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
- 26
- Survey
- Free, with a written quote
Single-storey extensions prices in West Yorkshire
Every figure below is a guide for a single-storey extension in West Yorkshire, inclusive of VAT. Regional pricing for Yorkshire and the Humber works out about 6% below the national guide, and the overall span is £33,000–£70,000. The survey costs you nothing, and after it we commit to a firm price for your specification in writing.
| Type of job | What it usually involves | Guide in West 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
- Ground conditions, foundation depth and drains to divert
- Steelwork needed to open into the existing house
- Finishes, kitchen, flooring and heating specification
What do you get?
- Groundworks, foundations and below-ground drainage
- 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 West Yorkshire
Leeds and Bradford are known for back-to-back and through terraces, many in sandstone or millstone grit, with stone-slate roofs on older properties. Halifax, Huddersfield and the Calder valley have mill-town stone terraces climbing steep hillsides, and interwar semis, post-war estates and newer housing surround the larger towns.
Back-to-backs and through terraces often suit dormer loft conversions and careful kitchen layouts. Stone properties commonly need repointing with suitable mortar, roof repairs and window replacement, and hillside plots can need retaining walls.
The Pennine hills bring high rainfall, wind and frost, and the Calder valley has a history of serious flooding.
Planning and building rules in West Yorkshire
Planning law differs across the UK. For a home in West Yorkshire, it is the England rules below that count, and we check them with the council ahead of any 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.
From survey to handover
We look at the job
We arrange a free site survey on a date convenient to you. We measure up, look at the existing structure and access, and discuss your plans for a single-storey extension so the price reflects your home.
Your fixed price
You get the price in writing, itemised so you can see where the money goes. As long as the specification stays the same, that is the price you pay for a single-storey extension.
Booking the work
Once you accept, we agree start dates, order materials and deal with any planning, building control or neighbour notices the job needs. You'll know who is coming and when before work begins.
On site to finish
The work is carried out to the agreed specification, with floors and furniture protected and the site kept tidy. At the end we clean up, walk through the finished job with you and hand over any certificates.
What you can expect from us
Frequently asked questions
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 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.
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.
Do I need planning permission in West 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. West 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.
Do you cover Leeds, Bradford and Huddersfield?
Yes. As well as West Yorkshire, we cover Leeds, Bradford and Huddersfield and the rest of West Yorkshire. Our coverage is UK-wide, so the process is the same wherever you are: a free site survey, a quote in writing that fixes the price for the agreed scope, and one point of contact while the work is planned and carried out.
Towns in West Yorkshire
Find your town below. Every place listed in West Yorkshire is covered for a single-storey extension, with the same survey, written quote and fixed-price process.

