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 Barrow in Furness?
In Barrow in Furness, a rooflight loft conversion typically costs £28,000–£42,500 for a typical rooflight conversion, including VAT at 20% (standard rate). We start from a UK-wide guide and adjust it for the North West, where labour and materials are typically about 6% below average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical rooflight conversion | £28,000–£42,500 |
| Higher specification | £42,500–£53,000 |
What moves the price most:
- Fire safety upgrades
- Bathroom or not
- Storage and finishes
- Staircase position
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 Barrow in Furness?
Whether you need planning permission depends on your house and its location 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
On a typical rooflight loft conversion we handle:
- Insulation between and under rafters
- Floor joists and any steel beams
- Electrics, heating and plastering
- Staircase and fire-safe escape route
- Roof windows installed
- Drawings and structural calculations
How long does it take?
Build time is typically 4 to 6 weeks on site. Allow time beforehand for drawings and approvals, usually 6 to 12 weeks.
Building in Barrow in Furness
Terraced streets across the North West often suit rear dormers and single-storey kitchen extensions.
From LA14 outwards, we take on projects throughout Barrow in Furness and the surrounding parts of Cumbria.
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
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about rooflight loft conversions in Barrow in Furness
Is it cheaper than a dormer?
Yes, usually, because the roof shape stays the same. But you gain less full-height floor space.
How long does it take?
Usually 4 to 6 weeks on site.
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.
Who approves a rooflight loft conversion in Barrow in Furness?
Planning matters in Barrow in Furness 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 Barrow in Furness?
In Barrow in Furness, a rooflight loft conversion typically costs £28,000–£42,500 for a typical rooflight conversion, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
