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 Clwyd?
In Clwyd, a hip-to-gable loft conversion typically costs £50,500–£72,000 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 Wales, where labour and materials are typically about 8% below average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A hip-to-gable with rear dormer | £50,500–£72,000 |
| Higher specification | £72,000–£90,000 |
The main things that change the cost:
- Size of the rear dormer
- Bathroom and plumbing
- Scaffolding to three sides
- Roof tile matching
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 Clwyd?
Approvals for a hip-to-gable loft conversion in Clwyd follow the rules for Wales. In Wales a hip-to-gable conversion may be permitted development within roof volume limits; corner plots and conservation areas usually need permission.
Building regulations in Wales are set by the Welsh Government. Approval comes from the council’s building control service or a registered building control approver, with inspections during the work and a completion certificate at the end.
We check this for your address before design work starts, so there are no surprises later.
What we handle
On a typical hip-to-gable loft conversion we handle:
- Staircase and fire-safe escape route
- Insulation, electrics, plumbing and plastering
- Gable wall built in brick or block and finished to match
- Survey and planning check
- Building control sign-off
- Drawings and structural calculations
How long does it take?
The build itself usually takes 7 to 10 weeks on site. Allow time beforehand for drawings and approvals, usually 6 to 12 weeks.
Building in Clwyd
Wales has many terraced valley streets, stone cottages and post-war estates, so extension designs are shaped by slopes, materials and local character.
Towns we cover in Clwyd include Wrexham, Deeside, Colwyn Bay, Flint, Rhyl and Hawarden.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and 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 Clwyd
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 Clwyd?
In Clwyd, a hip-to-gable loft conversion typically costs £50,500–£72,000 for a hip-to-gable with rear dormer, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
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 I need planning permission for a hip-to-gable loft conversion in Clwyd?
In Wales a hip-to-gable conversion may be permitted development within roof volume limits; corner plots and conservation areas usually need permission.
Can the gable be brick?
Yes. We match the existing finish, whether brick, render or pebbledash.
Who approves a hip-to-gable loft conversion in Clwyd?
Planning matters in Clwyd go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
