Double-storey extensions in Barnsley
From the first sketch to final sign-off, we plan and build double-storey extensions in Barnsley and the surrounding South Yorkshire area.
- Guide price in BarnsleyFrom £35,500 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsS70, S71, S75
How much does a double-storey extension cost in Barnsley?
For Barnsley we adjust our national guide rates by ×0.94, the factor we use for Yorkshire and the Humber. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Barnsley: £1,460 to £2,820 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m, two floors 24 m² | £35,500 – £43,000 | £40,500 – £53,500 | £51,500 – £68,000 |
| 4 m × 4 m, two floors 32 m² | £46,500 – £56,000 | £54,000 – £71,000 | £69,000 – £90,500 |
| 4 m × 6 m, two floors 48 m² | £69,500 – £83,500 | £81,000 – £106,500 | £103,500 – £135,500 |
Try the guide-price tool to see a range for your own size and finish.
When a double-storey extension makes sense
- Houses with enough distance to the rear or side boundary
- Homeowners who would otherwise consider moving
- Growing families who need a bedroom as well as a bigger kitchen
Planning rules that apply in Barnsley
In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.
The planning position for a specific Barnsley address depends on its history and any designations, which is why we check it at the first visit.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
Local to Barnsley
Site visits are available across Barnsley (S70, S71, S75). Neighbouring towns we cover include Darton (3 miles), Rawmarsh (8 miles), Rotherham (10 miles), Sheffield (12 miles).
Homes across Yorkshire and the Humber range from back-to-back and through terraces to large suburban semis, and extension options vary with them.
From first visit to completion
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
We visit your Barnsley home, measure up, talk through what you want and check the planning position.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Your questions about a double-storey extension in Barnsley
Do you cover all of Barnsley?
Yes. We cover Barnsley and the surrounding parts of South Yorkshire. Site visits are free and there is no obligation.
How long does a double-storey extension take to build in Barnsley?
On site, typically 16 to 24 weeks once approvals are in place. Before that, allow 8–16 weeks design and approvals.
Do I need building regulations approval in Barnsley?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Does a double-storey extension need planning permission?
Often, yes. In England a two-storey rear extension can be permitted development only if it projects no more than 3 m and sits at least 7 m from the rear boundary, with matching roof pitch and obscure side windows. Side extensions over one storey always need planning permission. We confirm the route at the survey.
Is a two-storey extension cheaper per square metre?
Usually. Our guide range is about £1,460 to £2,820 per m² of new floor area including VAT, compared with £1,640 to £3,200 per m² for single-storey work, because the foundations and roof are shared across two floors.
Book a free site visit in Barnsley
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.