Covering Doncaster
Alongside Doncaster, we also cover Bentley, Rotherham (11 miles to the south-west) and Pontefract.
Homes in Yorkshire and the Humber
Stone-built terraces are typical of many West Yorkshire towns, while red brick dominates in Hull and much of South Yorkshire, so matching materials is a big part of designing an extension here.
What goes into a basement conversion?
Everything below ground depends on keeping water out. We design the waterproofing system (usually a cavity drain membrane with a pump, or tanking) to the relevant British Standard guidance, then add insulation, ventilation, light and an escape route. New basements involve underpinning and a party wall process and are designed with a structural engineer.
- Damp and structural survey
- Waterproofing design and installation
- Finished floors, walls and ceilings
What is the guide price for a basement conversion in Doncaster?
Use these ranges to budget for basement and cellar conversions; the survey turns them into a fixed price for the agreed specification.
| Basement and cellar conversions | Guide price incl. VAT |
|---|---|
| Existing cellar conversion | £1,900 to £3,000 per m² |
| New basement excavation | £4,200 to £6,600 per m² |
Do you need permission for a basement conversion in Doncaster?
Projects in England go through two separate checks. Planning (or confirmation that the work is permitted development) comes from the district, borough or unitary council, and building regulations approval comes from the council’s building control team or a registered building control approver. Where work touches a shared wall or digs near a neighbour’s foundations, the Party Wall etc. Act 1996 applies.
Converting an existing cellar with no external changes usually does not need planning permission in England. Digging a new basement or adding a lightwell often does, and many councils have basement policies.
What should Doncaster homeowners check first?
- Groundwater levels drive the waterproofing design and cost.
- A pump for the drainage system needs a battery back-up.
What are the steps?
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
- Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
- Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.
Basement and cellar conversions: common questions
How much does a basement conversion cost?
Converting an existing cellar costs about £1,900 to £3,000 per square metre including VAT. A new excavated basement is around £4,200 to £6,600 per square metre.
Does a cellar conversion need planning permission?
Usually not if nothing changes outside. New basements and lightwells often do.
How do I get a price for basement and cellar conversions in Doncaster?
Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.
Basement and cellar conversions in nearby towns
- Basement and cellar conversions in Bentley
- Basement and cellar conversions in Rotherham
- Basement and cellar conversions in Pontefract
- Basement and cellar conversions in Royston
Learn more about basement and cellar conversions, or see every project we cover in Doncaster.

