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 Buckinghamshire?
In Buckinghamshire, a rooflight loft conversion typically costs £33,500–£50,500 for a typical rooflight conversion, including VAT at 20% (standard rate). Building costs in the South East run about 12% above the UK average, and the figures for Buckinghamshire are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical rooflight conversion | £33,500–£50,500 |
| Higher specification | £50,500–£63,000 |
The main things that change the cost:
- Staircase position
- Fire safety upgrades
- Number of roof windows
- Storage and finishes
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for a rooflight loft conversion in Buckinghamshire?
The approval route for Buckinghamshire is set by planning law 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.
If the answer is not clear-cut, we can apply for formal confirmation before you commit to the build.
What we handle
On a typical rooflight loft conversion we handle:
- Electrics, heating and plastering
- Roof windows installed
- Building control sign-off
- Drawings and structural calculations
- Insulation between and under rafters
- Staircase and fire-safe escape route
How long does it take?
Expect 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 Buckinghamshire
Commuter towns across the South East have many 1930s and post-war semis that suit rear extensions and hip-to-gable loft conversions.
Towns we cover in Buckinghamshire include Milton Keynes, High Wycombe, Aylesbury, Bletchley, Amersham and Chesham.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 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 Buckinghamshire
Can I have a bathroom?
Yes, where there is enough head height at the shower or bath position.
Do you build rooflight loft conversions in Buckinghamshire?
Yes. We build rooflight loft conversions across Buckinghamshire, including postcodes HP10, HP11, HP12, HP13 and HP14. Every project starts with a free home visit.
Is it cheaper than a dormer?
Yes, usually, because the roof shape stays the same. But you gain less full-height floor space.
How much does a rooflight loft conversion cost in Buckinghamshire?
In Buckinghamshire, a rooflight loft conversion typically costs £33,500–£50,500 for a typical rooflight conversion, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
How long does it take?
Usually 4 to 6 weeks on site.