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 Grays?
In Grays, a rooflight loft conversion typically costs £32,000–£47,500 for a typical rooflight conversion, including VAT at 20% (standard rate). That range is adjusted for the East of England, where domestic building work typically costs around 6% above the national average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical rooflight conversion | £32,000–£47,500 |
| Higher specification | £47,500–£59,500 |
What moves the price most:
- Bathroom or not
- Floor and roof strengthening
- Storage and finishes
- Fire safety upgrades
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 Grays?
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.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
Handled as part of most rooflight loft conversions:
- Floor joists and any steel beams
- Roof windows installed
- Electrics, heating and plastering
- Drawings and structural calculations
- Head-height survey
- Building control sign-off
How long does it take?
The build itself usually takes 4 to 6 weeks on site. Allow time beforehand for drawings and approvals, usually 6 to 12 weeks.
Building in Grays
Many towns in the East of England have estates built since the 1970s, where garage conversions and rear extensions are popular.
We work across Grays and neighbouring areas such as South Ockendon, Gravesend and Dartford. Postcodes we cover in Grays include RM17.
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
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about rooflight loft conversions in Grays
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 Grays?
In Grays, a rooflight loft conversion typically costs £32,000–£47,500 for a typical rooflight conversion, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
How long does a rooflight loft conversion take in Grays?
Typically 4 to 6 weeks on site. Design and approvals beforehand usually take 6 to 12 weeks.
What about fire safety?
The same escape rules apply as for any loft conversion, so a protected stairway and smoke alarms are typically needed.
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.
