Covering Willesden
Our coverage around Willesden (NW10) also includes Cricklewood (2 miles to the north-east) and Notting Hill.
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 goes into an upward extension?
An upward extension adds a new storey on top of an existing house, most often turning a bungalow into a two-storey or chalet-style home. It can double the floor area without using any of the garden.
- Design and planning or prior approval application
- New first-floor structure, walls and roof
- Staircase and changes to the ground floor layout
What will an upward extension cost?
What bungalow and upward extensions typically cost. These are guide ranges; the written quote for your house replaces them.
| Bungalow and upward extensions | Guide price incl. VAT |
|---|---|
| Chalet conversion with dormers (total) | £45,000 to £85,000 |
| New first floor, standard specification | £2,200 to £2,800 per m² |
| New first floor, good specification | £2,800 to £3,300 per m² |
| New first floor, high specification | £3,300 to £3,800 per m² |
Planning and building rules in Willesden
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.
In England, Class AA permitted development allows an extra storey on many detached and semi-detached houses built between July 1948 and October 2018, subject to a prior approval application covering design, neighbours’ amenity and other matters.
What can affect an upward extension?
- Some bungalow foundations need strengthening before a storey can be added.
- The staircase takes space from the ground floor plan.
How does the project run?
- 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.
- Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
Questions about an upward extension in Willesden
How much does it cost to add a storey?
Around £2,200 to £3,800 per square metre of new floor including VAT, or £45,000 to £85,000 for a chalet conversion with dormers.
How long does it take?
About 12 to 24 weeks on site.
Do you work in Willesden?
Yes. Willesden is within our coverage for bungalow and upward extensions, along with nearby Cricklewood and Notting Hill.
Also covering
- Bungalow and upward extensions in Cricklewood
- Bungalow and upward extensions in Notting Hill
- Bungalow and upward extensions in Shepherd's Bush
- Bungalow and upward extensions in Kilburn
Learn more about bungalow and upward extensions, or see every project we cover in Willesden.

