Covering Willesden
Willesden sits 5 miles west of London, with Cricklewood 2 miles to the north-east and Notting Hill 2 miles to the south-east.
Homes in London
Terraced houses dominate many London neighbourhoods, so most projects involve shared walls, narrow access and a party wall process. Conservation areas are widespread, and some boroughs have their own mansard and basement guidance.
What goes into a single-storey extension?
We design the extension around how you use the house: where the light comes from, how the new room joins the old one, and what happens to the drains and the garden. The structure is built in brick or block to match the house, finished with a flat roof and lantern or a pitched roof, then insulated, plastered and handed back ready to decorate.
- Measured survey and design drawings
- Building control application and inspections
- Brickwork, roof, glazing and insulation
What is the guide price for a single-storey extension in Willesden?
What single-storey extensions typically cost. These are guide ranges; the written quote for your house replaces them.
| Single-storey extensions | Guide price incl. VAT |
|---|---|
| Standard specification | £2,600 to £3,000 per m² |
| Good specification | £3,000 to £3,500 per m² |
| High specification | £3,500 to £4,000 per m² |
Do you need permission for a single-storey extension 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 a single-storey rear extension can often go ahead under permitted development: up to 3 m deep on an attached house or 4 m on a detached one, no higher than 4 m, with eaves no higher than 3 m within 2 m of a boundary.
What can change the price or programme?
- Building on or near a shared boundary usually means serving a party wall notice in England and Wales.
- Kitchens and doors have long lead times, so we order them early.
From first call to completion
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- 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.
- Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.
Questions about a single-storey extension in Willesden
Do I need planning permission for a single-storey extension?
Often not in England, if the extension stays within permitted development limits: 3 m deep on an attached house or 4 m on a detached house, and no higher than 4 m. Larger ones need prior approval or a planning application. Wales, Scotland and Northern Ireland have their own rules.
Do you need to dig up the drains?
Sometimes. If a public sewer runs under the extension, the water company has to agree a build-over or a diversion. We check this at survey stage.
Who deals with the council for a project in Willesden?
We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.
Single-storey extensions in nearby towns
- Single-storey extensions in Cricklewood
- Single-storey extensions in Notting Hill
- Single-storey extensions in Shepherd's Bush
- Single-storey extensions in Kilburn
Learn more about single-storey extensions, or see every project we cover in Willesden.

