What is a rooflight loft conversion?

A rooflight loft conversion (sometimes called a roof window conversion) keeps the existing roof shape and adds roof windows that sit flush with the slope. The floor is strengthened, a staircase is added and the space is insulated and finished.
How much does a rooflight loft conversion cost in Willesden?
In Willesden, a rooflight loft conversion typically costs £39,000–£58,500 for a typical rooflight conversion, including VAT at 20% (standard rate). The guide for Willesden reflects typical costs in London, roughly 30% above the UK-wide figure. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical rooflight conversion | £39,000–£58,500 |
| Higher specification | £58,500–£73,000 |
Your quote will depend mainly on:
- Number of roof windows
- Fire safety upgrades
- Storage and finishes
- Staircase position
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a rooflight loft conversion in Willesden?
Before anything is built in Willesden, we confirm which approvals apply in England. In England roof windows are permitted development if they project no more than 15 centimetres from the roof slope and side-facing windows are obscure-glazed. Listed buildings need consent.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
What we take care of:
- Building control sign-off
- Drawings and structural calculations
- Staircase and fire-safe escape route
- Roof windows installed
- Head-height survey
- Electrics, heating and plastering
How long does it take?
Allow 4 to 6 weeks on site. Allow time beforehand for drawings and approvals, usually 6 to 12 weeks.
Building in Willesden
Space is at a premium in London, so homeowners often build out into the side return or up into the roof rather than move.
Our Willesden coverage includes postcode districts NW10, and we also work in nearby places such as Acton, Hammersmith and Hampstead.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about rooflight loft conversions in Willesden
What about fire safety?
The same escape rules apply as for any loft conversion, so a protected stairway and smoke alarms are typically needed.
How much does a rooflight loft conversion cost in Willesden?
In Willesden, a rooflight loft conversion typically costs £39,000–£58,500 for a typical rooflight conversion, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Does a rooflight loft conversion need planning permission?
Usually not. In England roof windows are permitted development if they project no more than 15 centimetres from the roof slope, sit no higher than the ridge and any side-facing windows are obscure-glazed. Listed buildings and houses whose rights have been removed need consent. Building regulations approval is always needed.
How much head height do I need?
Around 2.2 metres or more from the top of the ceiling joists to the ridge is a good starting point. Insulation and new floor joists reduce the height.
Do you build rooflight loft conversions in Willesden?
Yes. We build rooflight loft conversions across Willesden, including postcodes NW10. Every project starts with a free home visit.
