Covering Ilford
Alongside Ilford, we also cover Barking, Becontree (2 miles to the east) and Leytonstone.
Homes in London
Much of London’s housing is Victorian and Edwardian terraces, which is why side return extensions, rear dormers and mansards are so common. Many streets are in conservation areas, and several boroughs use Article 4 directions that remove some permitted development rights.
What does a basement conversion involve?
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.
- Waterproofing design and installation
- Lightwells and windows for daylight and escape
- 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 |
What approvals does a basement conversion need in England?
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.
What should Ilford homeowners check first?
- Groundwater levels drive the waterproofing design and cost.
- New basements nearly always involve the Party Wall Act in England and Wales.
What are the steps?
- Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
- We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
Your questions answered
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 Ilford?
Yes. Ilford is within our coverage for basement and cellar conversions, along with nearby Barking and Becontree.
Also covering
- Basement and cellar conversions in Barking
- Basement and cellar conversions in Becontree
- Basement and cellar conversions in Leytonstone
- Basement and cellar conversions in Stratford
Learn more about basement and cellar conversions, or see every project we cover in Ilford.

