Two-storey extensions for detached houses in Bolton-upon-Dearne
For a two-storey extension for a detached house in Bolton-upon-Dearne, the first questions are always the same: how big, which approvals, and what it will cost. This page answers all three for South Yorkshire.
Before you start in Bolton-upon-Dearne, here's what applies.
- Postcode districts
- S63
- County / area
- South Yorkshire, England
- Price region
- Yorkshire and the Humber
- Guide price
- £79,000–£106,500 (£1,890–£2,530 per m²)
- Approval route
- Depends on position: a two-storey rear extension may be permitted development (3 m deep, 7 m from the rear boundary); a two-storey side extension needs planning permission.
- Nearest towns
- Wath-upon-Dearne (1.5 miles), Mexborough (1.9 miles), Wombwell (3.3 miles)
- Distance to Sheffield
- about 11.1 miles
- First visit
- Free, no obligation
About a two-storey extension for a detached house
A two-storey extension for a detached house is a two-floor addition to the side, rear or both of a house that stands on its own plot. Detached houses often have room on more than one side, so there is more choice of layout and fewer shared-wall issues. The design still needs to respect boundaries, neighbours' windows and the look of the house.
Around Bolton-upon-Dearne we also work in Wath-upon-Dearne, Mexborough and Wombwell, and across the rest of South Yorkshire. Postcode district in and near Bolton-upon-Dearne: S63.
What it costs in Bolton-upon-Dearne
In Yorkshire and the Humber, which includes Bolton-upon-Dearne, we'd expect a two-storey extension for a detached house to cost around £79,000–£106,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space), or £1,890–£2,530 per m² including VAT. These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.
| Spec | Per m² | A 3 m × 7 m footprint on two floors (42 m² of new floor space) |
|---|---|---|
| Essential | £1,740–£2,330 per m² | £73,000–£98,000 |
| Standard | £1,890–£2,530 per m² | £79,000–£106,500 |
| Premium | £2,260–£3,040 per m² | £95,000–£127,500 |
Planning and building regulations in Bolton-upon-Dearne
In England, a two-storey rear extension on a detached house can be permitted development within 3 m of the original rear wall and at least 7 m from the rear boundary, with matching roof pitch and materials, outside protected areas. Any two-storey side or wraparound extension needs planning permission, costing £548 (or £575 for applications made from 8 December 2026), with a decision due within 8 weeks of validation.
Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.
Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.
Design points for Bolton-upon-Dearne homes
Choosing the best side
On a detached house you can often extend on either side or the rear. We look at orientation for daylight, where the stairs and landing are, the distance to each boundary, drains and trees, so the extension goes where it adds the most useful space.
Larger spans and steelwork
Bigger extensions often mean wider openings and longer spans, which need more steel and sometimes a steel frame. The engineer designs these early, because the size of the steel affects ceiling heights, floor depths and the cost.
How we'd run your project
Look at the house
We start in Bolton-upon-Dearne with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.
Get it approved
Once you're happy with the design we submit it to the council for Bolton-upon-Dearne and deal with any questions from the planning officer.
Fixed price in writing
With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.
Finish and certify
Second fix, plastering and making good, then building control's final inspection and the completion paperwork.
Questions about two-storey extensions for detached houses in Bolton-upon-Dearne
How much does a two-storey extension for a detached house cost in Bolton-upon-Dearne?
Our guide for Yorkshire and the Humber, which covers Bolton-upon-Dearne, is £1,890–£2,530 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £79,000–£106,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.
Do I need planning permission for a two-storey extension for a detached house in Bolton-upon-Dearne?
Bolton-upon-Dearne is in England, so England planning rules apply. Depends on position: a two-storey rear extension may be permitted development (3 m deep, 7 m from the rear boundary); a two-storey side extension needs planning permission. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.
Who handles building regulations for a project in Bolton-upon-Dearne?
We handle it as part of the project. What's needed in England: building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.
How big an extension can a detached house take?
It depends on the plot, the boundaries and local design policy rather than a fixed limit. Under permitted development in England, extensions must not cover more than 50% of the land around the original house. With planning permission, the council judges size on proportion, neighbours and the character of the area.
Can I extend a detached house on both sides?
Sometimes. With planning permission, a council may accept extensions on both sides if the house stays well proportioned and keeps gaps to the boundaries. It is more common to extend on one side and the rear, or with a wraparound. We look at the plot as a whole before suggesting more than one extension.
Nearby
The same service in neighbouring towns:
Other extensions in Bolton-upon-Dearne
- Rear
- Side
- Wraparound
- Part two-storey
- Over a garage
- First floor
- Semi-detached
- Kitchen and bedrooms
- Bedroom and en-suite
All two-storey extension services in Bolton-upon-Dearne · Two-storey extensions for detached houses across South Yorkshire
Book a free site visit in Bolton-upon-Dearne and we'll tell you what's possible, what approvals you need and what the design stage would cost.