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.
Doncaster sits within our coverage for a double-storey extension, as do neighbouring Bentley, Adwick le Street and South Elmsall. Before giving a price we want to see the property: the condition of what's there now, the access, and anything that might need extra work. The guide range for Yorkshire and the Humber is £56,000–£113,000 including VAT, and your written quote will spell out exactly what that covers.
- Guide price
- £56,000–£113,000 inc VAT
- Time on site
- 14–22 weeks on site
- Postcodes
- DN1, DN2, DN4 and DN5
- Planning rules
- England
- Local area
- South Yorkshire
- Survey
- Free, with a written quote
Double-storey extensions prices in Doncaster
What will a double-storey extension cost in Doncaster? Our guide range is £56,000–£113,000 including VAT. That figure is adjusted for Yorkshire and the Humber, about 6% below the national guide, and is intended for planning a budget. A firm written price for your chosen specification follows a free survey at your home.
| Type of job | What it usually involves | Guide in Doncaster |
|---|---|---|
| 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 |
What moves the price up or down:
- Combined floor area across both storeys
- How the new roof joins the existing roof
- Bathrooms, en-suites and plumbing on the upper floor
- Foundation depth, ground conditions and drains to divert
What’s included?
- Groundworks, foundations and below-ground drainage
- Insulated cavity walls with brick or render to match the house
- Roof structure tied into the existing roof, tiled to match
- Electrics, plumbing and heating by qualified trades, with certificates
- Windows, external doors, plastering and internal doors
- Building control inspections and completion certificate
What are homes like around Doncaster?
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.
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.
If your house in Doncaster fits one of these patterns, it helps us anticipate what a double-storey extension will involve, though we always confirm the details on site.
Do you need permission in Doncaster?
As Doncaster is in England, read the following with that system of planning and building control in mind. We check what applies to your house with the council before you receive a quote.
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.
What happens after you get in touch?
Survey and measure
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
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.
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 Doncaster property.
Build and hand over
Work goes ahead as scheduled and you deal with one contact throughout. When the last trade leaves, we clear and clean the site, talk you through what has been done and pass on any certificates and care instructions.
How we work
Questions about a double-storey extension in Doncaster
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.
How long will a double-storey extension take?
On a typical home, allow 14–22 weeks on site. Larger projects, older buildings and extra work found once things are opened up can extend that, while simpler jobs may be shorter. Your quote includes an estimate of time on site, and your point of contact keeps you updated on the programme as the work progresses.
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.
How long does a double-storey extension take?
A double-storey extension typically takes 14–22 weeks on site, depending on size, roof design and weather. Foundations and ground-floor walls come first, then the first-floor joists, upper walls and roof. Once it is weathertight, electrics, plumbing, plastering and finishes follow. Allow extra time beforehand for drawings, calculations and approvals. We give you a stage-by-stage programme with your quote.
Is a double-storey extension better value than single-storey?
A double-storey extension usually gives better value per square metre than a single-storey one, because the same foundations and roof serve twice the floor area. The overall cost is higher, and planning can be harder because of the effect on neighbours. If you might want an extra bedroom later, building both floors now avoids a second round of disruption and scaffolding.
Nearby towns
We survey and quote throughout Doncaster's DN1, DN2, DN4 and DN5 postcodes and in surrounding places such as Bentley, Adwick le Street and South Elmsall. The process and pricing approach are identical in each of them.