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 Caerphilly?
In Caerphilly, 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). That range is adjusted for Wales, where domestic building work typically costs around 8% below the national 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 |
Your quote will depend mainly on:
- Scaffolding to three sides
- Gable wall construction and finish
- Bathroom and plumbing
- Size of the rear dormer
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a hip-to-gable loft conversion in Caerphilly?
Whether you need planning permission depends on your house and its location in 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.
Our first visit includes a check of your planning history, so you know the route before paying for drawings.
What we handle
Handled as part of most hip-to-gable loft conversions:
- Insulation, electrics, plumbing and plastering
- Survey and planning check
- Roof extension and rear dormer
- Building control sign-off
- Gable wall built in brick or block and finished to match
- Staircase and fire-safe escape route
How long does it take?
Allow 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 Caerphilly
Wales has many terraced valley streets, stone cottages and post-war estates, so extension designs are shaped by slopes, materials and local character.
Caerphilly sits in Mid Glamorgan, about 7 miles north of Cardiff. We cover the whole of Caerphilly, including postcodes CF83.
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
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 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 Caerphilly
How much does a hip-to-gable loft conversion cost in Caerphilly?
In Caerphilly, 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 I need building regulations approval?
Yes. All loft conversions to habitable rooms need building control approval for structure, fire safety, insulation and stairs.
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.
Who approves a hip-to-gable loft conversion in Caerphilly?
Planning matters in Caerphilly go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
How long does it take?
Typically 7 to 10 weeks on site.
Do I need planning permission for a hip-to-gable loft conversion in Caerphilly?
In Wales a hip-to-gable conversion may be permitted development within roof volume limits; corner plots and conservation areas usually need permission.