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 Hitchin?
In Hitchin, a hip-to-gable loft conversion typically costs £58,500–£82,500 for a hip-to-gable with rear dormer, 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 hip-to-gable with rear dormer | £58,500–£82,500 |
| Higher specification | £82,500–£103,000 |
The main things that change the cost:
- Scaffolding to three sides
- Staircase design
- Bathroom and plumbing
- Size of the rear dormer
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 Hitchin?
The approval route for Hitchin 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
From survey to sign-off, the job normally involves:
- Survey and planning check
- Building control sign-off
- Insulation, electrics, plumbing and plastering
- Steel beams and floor joists
- Roof extension and rear dormer
- Staircase and fire-safe escape route
How long does it take?
The build itself usually takes 7 to 10 weeks on site. Design and approvals come first and typically take 6 to 12 weeks, depending on the approval route.
Building in Hitchin
Many towns in the East of England have estates built since the 1970s, where garage conversions and rear extensions are popular.
Hitchin sits in Hertfordshire, about 14 miles north-west of Hertford. We cover the whole of Hitchin, including postcodes SG4 and SG5.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 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 Hitchin
How long does a hip-to-gable loft conversion take in Hitchin?
Typically 7 to 10 weeks on site. Design and approvals beforehand usually take 6 to 12 weeks.
Will it look strange next to my neighbour?
On a pair of semis the roofs will no longer match unless your neighbour does the same. Many streets already have several converted roofs.
Can the gable be brick?
Yes. We match the existing finish, whether brick, render or pebbledash.
How much does a hip-to-gable loft conversion cost in Hitchin?
In Hitchin, a hip-to-gable loft conversion typically costs £58,500–£82,500 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.
