Local costs · North West · September 2026
How much does an extension cost in Oldham?
A mid-range 25 m² single-storey extension in Oldham costs about £58,500 to £72,500 including VAT, or £2,300 to £2,900 per m² at North West prices. Oldham 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 £73,000 to £95,000.
Work out your project in Oldham
Loading the calculator…
Typical prices in Oldham
| Project | Building work | Budget to plan for |
|---|---|---|
| Single-storey extension, 25 m² | £58,500 to £72,500 | £73,000 to £95,000 |
| Double-storey extension, 40 m² | £85,000 to £107,000 | £105,000 to £137,000 |
| Dormer loft conversion, 30 m² | £52,500 to £64,500 | £65,500 to £84,000 |
| Kitchen, medium | £8,700 to £15,400 | £10,000 to £17,800 |
| Bathroom refit | £5,700 to £8,600 | £6,600 to £9,900 |
Building prices in North West run about 7% below the UK average outside London. Kitchens and bathrooms vary less from place to place than extensions and lofts.
Building control fees in Oldham
| Work | Charge |
|---|---|
| Extension up to 10 m² (full plans) | £506 |
| Extension 10 to 40 m² (full plans) | £665 |
| Larger extension, 40-80 m² (full plans) | £861 |
| Extension 10 to 40 m² (building notice) | £730 |
| Loft conversion up to 40 m² | £712 |
| Garage conversion | Not published |
Oldham 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: Oldham's building control charges, 1 April 2025. Inc VAT totals.
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 Oldham compares with every council we checked.
Notes on Oldham's schedule
Own page. <=10 m2 is a single charge. Loft figure is with dormer (without 531). Garage conversion row not captured.
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 North West
Building control for a 10 to 40 m² extension:
- Blackpool: £654
- Fylde: £660
- Bury: £713
- Wyre: £714
- Ribble Valley: £718
- Cheshire West and Chester: £736
- Pendle: £756
- Liverpool: £822
- Stockport: £1,050
Questions people ask
How much does an extension cost in Oldham?
A mid-range 25 m² single-storey extension in Oldham costs about £58,500 to £72,500 including VAT for the building work, or £2,300 to £2,900 per m², based on North West prices reviewed in September 2026. With fees and a 15% contingency, budget £73,000 to £95,000.
How much is building control in Oldham?
Oldham charges £665 (including VAT) for a 10 to 40 m² extension (full plans), according to its published schedule (1 April 2025).
How much does a loft conversion cost in Oldham?
A mid-range 30 m² dormer loft conversion in Oldham costs about £52,500 to £64,500 including VAT for the building work, and about £65,500 to £84,000 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