What is a hip-to-gable loft conversion?
A hip-to-gable loft conversion replaces the sloping side (the hip) of a semi-detached or detached roof with a vertical gable wall. This extends the ridge and creates enough space for a staircase and a full-size room, usually combined with a rear dormer.
How much does a hip-to-gable loft conversion cost in Chiswick?
In Chiswick, a hip-to-gable loft conversion typically costs £71,500–£101,500 for a hip-to-gable with rear dormer, including VAT at 20% (standard rate). The guide for Chiswick 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 hip-to-gable with rear dormer | £71,500–£101,500 |
| Higher specification | £101,500–£127,000 |
What moves the price most:
- Staircase design
- Roof tile matching
- Size of the rear dormer
- Scaffolding to three sides
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for a hip-to-gable loft conversion in Chiswick?
The approval route for Chiswick is set by planning law in England. In England a hip-to-gable conversion is often permitted development within the 50 cubic metre roof volume limit for semi-detached and detached houses, provided the gable does not face a road and the house is not in a conservation area.
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:
- Gable wall built in brick or block and finished to match
- Insulation, electrics, plumbing and plastering
- Steel beams and floor joists
- Roof extension and rear dormer
- Staircase and fire-safe escape route
- Building control sign-off
How long does it take?
Build time is typically 7 to 10 weeks on site. Before that, surveys, drawings and approvals usually take 6 to 12 weeks, longer if the council asks for changes.
Building in Chiswick
Space is at a premium in London, so homeowners often build out into the side return or up into the roof rather than move.
Projects in Chiswick (W4) are surveyed in person before we quote, so the price reflects your actual property.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 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 hip-to-gable loft conversions in Chiswick
How much does a hip-to-gable loft conversion cost in Chiswick?
In Chiswick, a hip-to-gable loft conversion typically costs £71,500–£101,500 for a hip-to-gable with rear dormer, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
How long does a hip-to-gable loft conversion take in Chiswick?
Typically 7 to 10 weeks on site. Design and approvals beforehand usually take 6 to 12 weeks.
Can the gable be brick?
Yes. We match the existing finish, whether brick, render or pebbledash.
Is a hip-to-gable conversion permitted development?
Often yes in England, within the 50 cubic metre roof volume limit for semi-detached and detached houses. It is not permitted development in conservation areas or where rights have been removed.
Is a hip-to-gable better than a dormer?
On a hipped roof, a dormer alone often leaves too little space for stairs. Combining hip-to-gable with a rear dormer gives the most room.