Covering Leytonstone
We work in Leytonstone (E11) and the places around it, including Walthamstow, Stratford and Ilford.
Homes in London
London projects often mean working on period terraces with neighbours on both sides, tight access through the house and conservation area controls, so careful planning and party wall work matter as much as the build.
What do you get with 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.
- Damp and structural survey
- Waterproofing design and installation
- Ventilation, heating and electrics
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 |
How is a basement conversion approved in Leytonstone?
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 should Leytonstone homeowners check first?
- 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 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.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
What people ask before starting
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.
Can you visit a house in Leytonstone 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.
Basement and cellar conversions near Leytonstone
- Basement and cellar conversions in Walthamstow
- Basement and cellar conversions in Stratford
- Basement and cellar conversions in Ilford
- Basement and cellar conversions in Woodford Green
Learn more about basement and cellar conversions, or see every project we cover in Leytonstone.

