Covering Middlesbrough
Alongside Middlesbrough, we also cover Billingham, Stockton-on-Tees (3 miles to the west) and Thornaby-on-Tees.
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.
- Underpinning or lowering the floor where needed
- Ventilation, heating and electrics
- Finished floors, walls and ceilings
How much should I budget for a basement conversion?
Indicative costs for basement and cellar conversions. London and the South East usually sit towards the top of each range.
| 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 Middlesbrough
In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it 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 can change the price or programme?
- Groundwater levels drive the waterproofing design and cost.
- Headroom of about 2.1 m or more is needed, which may mean lowering the floor.
What happens after I enquire?
- 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.
What people ask before starting
Does a cellar conversion need planning permission?
Usually not if nothing changes outside. New basements and lightwells often do.
How do you keep a basement dry?
With a designed waterproofing system, usually a cavity drain membrane draining to a pump, sometimes combined with tanking.
Do you work in Middlesbrough?
Yes. Middlesbrough is within our coverage for basement and cellar conversions, along with nearby Billingham and Stockton-on-Tees.
Basement and cellar conversions in nearby towns
- Basement and cellar conversions in Billingham
- Basement and cellar conversions in Stockton-on-Tees
- Basement and cellar conversions in Thornaby-on-Tees
- Basement and cellar conversions in Redcar
Learn more about basement and cellar conversions, or see every project we cover in Middlesbrough.

