Local costs · Yorkshire and the Humber · September 2026
How much does an extension cost in Barnsley?
A mid-range 25 m² single-storey extension in Barnsley costs about £58,000 to £72,000 including VAT, or £2,300 to £2,900 per m² at Yorkshire and the Humber prices. Barnsley charges £665 for building control on a 10 to 40 m² extension (full plans, including VAT): the 9th cheapest of the 91 councils we checked, 21% below the typical council (£840). With design, a structural engineer, building control and a 15% contingency, budget £72,500 to £94,000.
Work out your project in Barnsley
Loading the calculator…
Typical prices in Barnsley
| Project | Building work | Budget to plan for |
|---|---|---|
| Single-storey extension, 25 m² | £58,000 to £72,000 | £72,500 to £94,000 |
| Double-storey extension, 40 m² | £84,000 to £106,000 | £104,000 to £136,000 |
| Dormer loft conversion, 30 m² | £52,000 to £64,000 | £65,000 to £83,500 |
| Kitchen, medium | £8,600 to £15,400 | £9,900 to £17,700 |
| Bathroom refit | £5,700 to £8,600 | £6,600 to £9,900 |
Building prices in Yorkshire and the Humber run about 8% below the UK average outside London. Kitchens and bathrooms vary less from place to place than extensions and lofts.
Building control fees in Barnsley
| Work | Charge |
|---|---|
| Extension up to 10 m² (full plans) | £465 |
| Extension 10 to 40 m² (full plans) | £665 |
| Larger extension, 40-60 m² (full plans) | £780 |
| Extension 10 to 40 m² (building notice) | £665 |
| Loft conversion up to 40 m² | £655 |
| Garage conversion | £390 |
Barnsley charges £665 for building control on a 10 to 40 m² extension (full plans, including VAT): the 9th cheapest of the 91 councils we checked, 21% below the typical council (£840). Source: Barnsley's building control charges, 6 April 2026. Inc VAT ("All fees quoted include V.A.T. @ 20%").
Private approved inspectors set their own prices and are often competitive, so it is worth asking one or two for a quote as well. See how Barnsley compares with every council we checked.
Notes on Barnsley's schedule
Own schedule. Loft figure is roof-space rooms with new access (without 530). Garage conversion has nil inspection charge.
Planning
If your extension needs planning permission, a householder application in England costs £548. Many single-storey rear extensions are permitted development and need no application, and a lawful development certificate (£274) confirms it.
Other councils in Yorkshire and the Humber
Building control for a 10 to 40 m² extension:
Questions people ask
How much does an extension cost in Barnsley?
A mid-range 25 m² single-storey extension in Barnsley costs about £58,000 to £72,000 including VAT for the building work, or £2,300 to £2,900 per m², based on Yorkshire and the Humber prices reviewed in September 2026. With fees and a 15% contingency, budget £72,500 to £94,000.
How much is building control in Barnsley?
Barnsley charges £665 (including VAT) for a 10 to 40 m² extension (full plans), according to its published schedule (6 April 2026).
How much does a loft conversion cost in Barnsley?
A mid-range 30 m² dormer loft conversion in Barnsley costs about £52,000 to £64,000 including VAT for the building work, and about £65,000 to £83,500 with fees and a 15% contingency.
Before you get quotes
- How to compare builders' quotes line by line
- Plan your whole budget, including the costs people forget
- Trades: price an extension element by element with editable unit rates