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 Southall?
In Southall, 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 Southall 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:
- Scaffolding to three sides
- Bathroom and plumbing
- Size of the rear dormer
- Roof tile matching
Use the guide price tool to see how size and specification change the figure, then ask for a written, itemised quote.
Do you need planning permission for a hip-to-gable loft conversion in Southall?
The approval route for Southall 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.
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.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
The work we manage on a hip-to-gable loft conversion:
- Roof extension and rear dormer
- Survey and planning check
- Insulation, electrics, plumbing and plastering
- Steel beams and floor joists
- Gable wall built in brick or block and finished to match
- Staircase and fire-safe escape route
How long does it take?
Expect 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 Southall
Victorian and Edwardian terraces dominate many London streets, which is why side return, wraparound and mansard projects are so common here.
From UB1 outwards, we take on projects throughout Southall and the surrounding parts of Greater London.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about hip-to-gable loft conversions in Southall
Who approves a hip-to-gable loft conversion in Southall?
Planning matters in Southall 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 Southall?
In Southall, 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.
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.
How long does it take?
Typically 7 to 10 weeks on site.
Will I need building regulations approval?
Yes. All loft conversions to habitable rooms need building control approval for structure, fire safety, insulation and stairs.
