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 Milton Keynes?
In Milton Keynes, a hip-to-gable loft conversion typically costs £61,500–£87,500 for a hip-to-gable with rear dormer, including VAT at 20% (standard rate). Building costs in the South East run about 12% above the UK average, and the figures for Milton Keynes are adjusted to reflect that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A hip-to-gable with rear dormer | £61,500–£87,500 |
| Higher specification | £87,500–£109,500 |
The biggest cost drivers are:
- Size of the rear dormer
- Gable wall construction and finish
- Bathroom and plumbing
- Roof tile matching
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 Milton Keynes?
The approval route for Milton Keynes 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.
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:
- Gable wall built in brick or block and finished to match
- Steel beams and floor joists
- Staircase and fire-safe escape route
- Insulation, electrics, plumbing and plastering
- Roof extension and rear dormer
- Drawings and structural calculations
How long does it take?
Allow 7 to 10 weeks on site. Allow time beforehand for drawings and approvals, usually 6 to 12 weeks.
Building in Milton Keynes
Commuter towns across the South East have many 1930s and post-war semis that suit rear extensions and hip-to-gable loft conversions.
Projects in Milton Keynes (MK1, MK4, MK6 and MK8) 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
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 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 Milton Keynes
How much does a hip-to-gable loft conversion cost in Milton Keynes?
In Milton Keynes, a hip-to-gable loft conversion typically costs £61,500–£87,500 for a hip-to-gable with rear dormer, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Can the gable be brick?
Yes. We match the existing finish, whether brick, render or pebbledash.
Do you build hip-to-gable loft conversions in Milton Keynes?
Yes. We build hip-to-gable loft conversions across Milton Keynes, including postcodes MK1, MK4, MK6 and MK8. Every project starts with a free home visit.
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.
