A double-storey extension adds two floors of new space to your house in one build, typically a larger kitchen or living room downstairs with an extra bedroom, bathroom or en-suite above, sharing one set of foundations and one roof.
Across South Yorkshire, people look into a double-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 Sheffield, Rotherham, Doncaster and Barnsley and the smaller towns around them, working to the rules that apply in England. Expect a guide of £56,000–£113,000, VAT included, in Yorkshire and the Humber, and every quote follows a free visit.
- Guide price
- £56,000–£113,000 inc VAT
- Time on site
- 14–22 weeks on site
- Planning rules
- England
- Price level
- About 6% below the national guide
- Towns listed
- 13
- Survey
- Free, with a written quote
How much does a double-storey extension cost in South Yorkshire?
Prices for a double-storey extension vary from house to house, but in South Yorkshire most projects fall within £56,000–£113,000 including VAT. That reflects costs in Yorkshire and the Humber, about 6% below the national guide. Treat the table as a budgeting aid; the written figure follows a survey we carry out for free.
| Type of job | What it usually involves | Guide in South Yorkshire |
|---|---|---|
| Small (15–20m² total) | A compact rear or side extension adding a small room on each floor. | £37,500–£61,000 |
| Typical (30–40m² total) | A larger kitchen or living room below with a double bedroom or en-suite above. | £56,000–£113,000 |
| Large (50m² plus total) | Wide or deep extensions, often with a new bathroom, steelwork and high-spec glazing. | £94,000–£169,000 |
The main things that change the figure:
- Combined floor area across both storeys
- How the new roof joins the existing roof
- Foundation depth, ground conditions and drains to divert
- Scaffolding duration, access and the level of finishes
What’s included?
- Groundworks, foundations and below-ground drainage
- Insulated cavity walls with brick or render to match the house
- First-floor joists, stud walls and new openings upstairs
- Scaffolding for the full build, erected and inspected
- Electrics, plumbing and heating by qualified trades, with certificates
- Building control inspections and completion certificate
Homes in South Yorkshire
Sheffield's housing climbs steep hillsides, with Victorian brick terraces, stone villas in the western suburbs and large interwar and post-war council estates. Barnsley, Rotherham and Doncaster have long rows of colliery-era brick terraces, post-war housing including some non-traditional construction, and newer estates continue to grow around Doncaster.
Terraces often suit loft conversions and rear extensions, and steep plots can call for retaining walls, steps and terraced patios. Older homes commonly need repointing, window replacement and roof work.
The Pennine edge brings heavy rain and cold winds, river valleys such as the Don have a history of flooding, and old mine workings can affect ground.
Planning and building rules in South Yorkshire
Because South Yorkshire falls under England's rules, the guidance below is the version relevant to you. Before sending a price, we check your property's position with the council.
In England, a two-storey rear extension can only be permitted development if it is no more than 3 m deep, at least 7 m from the rear boundary and finished to match the house. Most double-storey and all two-storey side extensions need full planning permission.
Building Regulations approval is needed, with structural calculations for beams, foundations and the roof. The Party Wall etc. Act 1996 often applies on semi-detached and terraced houses.
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
We begin by looking at the job in person. During the free survey we discuss options, materials and budget for a double-storey extension, and photograph or measure anything the quote needs to reflect.
Written quote
The quote arrives in writing, not over the phone. It covers the full scope, the finishes you've chosen, any exclusions and the payment schedule, with a fixed price tied to that specification.
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.
Finish and handover
Our trades complete a double-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.
What you can expect from us
Frequently asked questions
Is the price fixed?
Yes, for the specification we agree. Your written quote sets out exactly what is included at a fixed price. It only changes if you ask for something different, or if a problem the survey could not reasonably reveal later needs extra work. In either case we explain the change and confirm it in writing before going ahead.
Which postcodes in South Yorkshire do you cover?
We cover S1, S60, DN1 and S70, along with the rest of South Yorkshire. If your postcode is not listed, get in touch anyway: our coverage is UK-wide, and we can usually arrange a survey wherever you live. Enter your postcode in the guide-price tool or contact form and we will confirm.
Can the new upstairs room have its own bathroom?
A new upstairs room can usually have an en-suite, provided waste pipes can reach the soil stack or a new one can be installed. Running the waste pipe to the right falls is the main design question, and a pumped system is an option where gravity will not work. We plan bathroom positions at the design stage so pipes, ventilation and insulation are built in rather than added later.
Will the extension affect my neighbours?
A double-storey extension can affect neighbours' light, outlook and privacy, which is why planning departments look closely at height, depth and window positions. Side windows facing neighbours often need obscure glass. Work near a shared wall may also need party wall notices; the Party Wall etc. Act 1996 applies in England and Wales only. We talk through these points early so the design is realistic.
Can we live at home while it is built?
Most families stay at home during a double-storey extension. The new structure is built outside first, and we only break through into the existing rooms near the end, usually one floor at a time. Upstairs, this may mean a bedroom is out of use for a week or two. We fit dust screens, protect floors and stairs, and plan any time without water or power in advance.
Towns in South Yorkshire
Find your town below. Every place listed in South Yorkshire is covered for a double-storey extension, with the same survey, written quote and fixed-price process.