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 Mangotsfield?
In Mangotsfield, a hip-to-gable loft conversion typically costs £56,000–£79,500 for a hip-to-gable with rear dormer, including VAT at 20% (standard rate). Building costs in the South West are close to the UK average, so the figures for Mangotsfield are close to our national guide. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A hip-to-gable with rear dormer | £56,000–£79,500 |
| Higher specification | £79,500–£99,500 |
Your quote will depend mainly on:
- Bathroom and plumbing
- Scaffolding to three sides
- Roof tile matching
- Gable wall construction and finish
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 hip-to-gable loft conversion in Mangotsfield?
Before anything is built in Mangotsfield, we confirm which approvals apply 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.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
If the answer is not clear-cut, we can apply for formal confirmation before you commit to the build.
What we handle
What we take care of:
- Survey and planning check
- Insulation, electrics, plumbing and plastering
- Drawings and structural calculations
- Building control sign-off
- Gable wall built in brick or block and finished to match
- Staircase and fire-safe escape route
How long does it take?
The build itself usually takes 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 Mangotsfield
In parts of the South West, protected landscapes and conservation areas shape what can be built, so materials and roof forms are chosen carefully.
From BS16 outwards, we take on projects throughout Mangotsfield and the surrounding parts of Gloucestershire.
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 hip-to-gable loft conversions in Mangotsfield
Can the gable be brick?
Yes. We match the existing finish, whether brick, render or pebbledash.
How long does it take?
Typically 7 to 10 weeks on site.
Who approves a hip-to-gable loft conversion in Mangotsfield?
Planning matters in Mangotsfield 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 hip-to-gable loft conversion cost in Mangotsfield?
In Mangotsfield, a hip-to-gable loft conversion typically costs £56,000–£79,500 for a hip-to-gable with rear dormer, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Will I need building regulations approval?
Yes. All loft conversions to habitable rooms need building control approval for structure, fire safety, insulation and stairs.
