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 Corby?
In Corby, a hip-to-gable loft conversion typically costs £52,000–£74,000 for a hip-to-gable with rear dormer, including VAT at 20% (standard rate). We start from a UK-wide guide and adjust it for the East Midlands, where labour and materials are typically about 5% below average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A hip-to-gable with rear dormer | £52,000–£74,000 |
| Higher specification | £74,000–£92,500 |
The main things that change the cost:
- Bathroom and plumbing
- Gable wall construction and finish
- Scaffolding to three sides
- Size of the rear dormer
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 Corby?
Before anything is built in Corby, 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.
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
On a typical hip-to-gable loft conversion we handle:
- Building control sign-off
- Gable wall built in brick or block and finished to match
- Insulation, electrics, plumbing and plastering
- Staircase and fire-safe escape route
- Drawings and structural calculations
- Roof extension and rear dormer
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 Corby
The East Midlands has a mix of red-brick terraces, inter-war semis and newer estates, so rear extensions and garage conversions are common projects.
Projects in Corby (NN17) are surveyed in person before we quote, so the price reflects your actual property.
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 Corby
Will I need building regulations approval?
Yes. All loft conversions to habitable rooms need building control approval for structure, fire safety, insulation and stairs.
How much does a hip-to-gable loft conversion cost in Corby?
In Corby, a hip-to-gable loft conversion typically costs £52,000–£74,000 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 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.
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.
Do you build hip-to-gable loft conversions in Corby?
Yes. We build hip-to-gable loft conversions across Corby, including postcodes NN17. Every project starts with a free home visit.
