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 Teddington?
In Teddington, a rooflight loft conversion typically costs £39,000–£58,500 for a typical rooflight conversion, including VAT at 20% (standard rate). Prices across London are typically 30% above the UK average for this kind of work, which is reflected in the range for Teddington. 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 |
The biggest cost drivers are:
- Storage and finishes
- Staircase position
- Fire safety upgrades
- Number of roof windows
Use the guide price tool to see how size and specification change the figure, then ask for a written, itemised quote.
Do you need planning permission for a rooflight loft conversion in Teddington?
Before anything is built in Teddington, 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.
We check this for your address before design work starts, so there are no surprises later.
What we handle
What we take care of:
- Roof windows installed
- Head-height survey
- Staircase and fire-safe escape route
- Floor joists and any steel beams
- Electrics, heating and plastering
- Insulation between and under rafters
How long does it take?
Build time is typically 4 to 6 weeks on site. Before that, surveys, drawings and approvals usually take 6 to 12 weeks, longer if the council asks for changes.
Building in Teddington
Space is at a premium in London, so homeowners often build out into the side return or up into the roof rather than move.
If your home is in Teddington or close by in Kingston upon Thames, Twickenham and East Molesey, a free home visit is the first step.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 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 Teddington
Can I have a bathroom?
Yes, where there is enough head height at the shower or bath position.
How long does it take?
Usually 4 to 6 weeks on site.
Who approves a rooflight loft conversion in Teddington?
Planning matters in Teddington go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
How much does a rooflight loft conversion cost in Teddington?
In Teddington, 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.
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.