Covering Heston
Alongside Heston, we also cover Hounslow, Isleworth (2 miles to the east) and Southall.
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
- Underpinning or lowering the floor where needed
- Lightwells and windows for daylight and escape
What is the guide price for a basement conversion in Heston?
What basement and cellar conversions typically cost. These are guide ranges; the written quote for your house replaces them.
| 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 Heston
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 I think about before starting?
- New basements nearly always involve the Party Wall Act in England and Wales.
- A pump for the drainage system needs a battery back-up.
What happens after I enquire?
- Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
- We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
- Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
- 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 long does it take?
About 6 to 12 weeks for a cellar conversion and 16 to 30 weeks for a new basement.
How do I get a price for basement and cellar conversions in Heston?
Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.
Also covering
- Basement and cellar conversions in Hounslow
- Basement and cellar conversions in Isleworth
- Basement and cellar conversions in Southall
- Basement and cellar conversions in Hayes
Learn more about basement and cellar conversions, or see every project we cover in Heston.

