Covering Eastleigh
We work in Eastleigh (SO50, SO97) and the places around it, including Southampton, Winchester and Totton.
Homes in the South East
Many South East homes are inter-war or post-war semis and detached houses with room for rear and side extensions, while historic town centres and villages bring conservation area and listed building controls.
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.
- 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 |
How is a basement conversion approved in Eastleigh?
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 can affect a basement conversion?
- Groundwater levels drive the waterproofing design and cost.
- A pump for the drainage system needs a battery back-up.
How does the project run?
- Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.
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.
Does a cellar conversion need planning permission?
Usually not if nothing changes outside. New basements and lightwells often do.
Who deals with the council for a project in Eastleigh?
We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.
Also covering
- Basement and cellar conversions in Southampton
- Basement and cellar conversions in Winchester
- Basement and cellar conversions in Totton
- Basement and cellar conversions in Fareham
Learn more about basement and cellar conversions, or see every project we cover in Eastleigh.