Covering Northumberland
Our basement and cellar conversions service in Northumberland covers Blyth, Cramlington, Ashington and Bedlington and more.
Projects in Northumberland are taken on by arrangement, and any travel and accommodation costs for the team are shown openly in the quote.
Homes in the North East
Housing across the North East ranges from colliery terraces and Tyneside flats to suburban semis and modern estates, each with different options for extending.
What goes into a basement conversion?
A basement conversion turns an existing cellar into dry, usable rooms, or excavates a new basement under a house. Converting an existing cellar is far simpler and cheaper than digging a new one, and often does not need planning permission.
- Lightwells and windows for daylight and escape
- Ventilation, heating and electrics
- Finished floors, walls and ceilings
What will a basement conversion cost?
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 |
Planning and building rules in Northumberland
English projects need planning clearance from the local council, building regulations sign-off from building control, and party wall notices where the work is on or near a shared boundary. We prepare and manage all three.
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 Northumberland homeowners check first?
- Groundwater levels drive the waterproofing design and cost.
- New basements nearly always involve the Party Wall Act in England and Wales.
How does the project run?
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
Your questions answered
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.
How long does it take?
About 6 to 12 weeks for a cellar conversion and 16 to 30 weeks for a new basement.
Can you visit a house in Northumberland to quote?
Yes. After a short call we arrange a site visit to measure up and agree what the design needs to do, then send a written price.
Also covering
- Basement and cellar conversions in Blyth
- Basement and cellar conversions in Cramlington
- Basement and cellar conversions in Ashington
- Basement and cellar conversions in Bedlington
- Basement and cellar conversions in Morpeth
- Basement and cellar conversions in Hexham
- Basement and cellar conversions in Alnwick
Learn more about basement and cellar conversions, or see every project we cover in Northumberland.

