Covering Cardiff
Alongside Cardiff, we also cover Whitchurch (3 miles to the north-west), Penarth and Caerphilly.
Homes in South Glamorgan
Welsh homes include long terraces built into hillsides, stone cottages and modern estates, and sloping sites often shape how and where an extension can go.
What is included in a dormer loft conversion in Cardiff?
A dormer loft conversion builds a box-shaped extension out from the rear slope of the roof, creating vertical walls and full head height across most of the new floor. It is the most popular type of loft conversion because it gives the most usable space for the cost.
- Planning and building regulations checks under Welsh rules
- Staircase, insulation and plasterboard
- En-suite, electrics and fire-protected escape route
How much should I budget for a dormer loft conversion?
Typical ranges for dormer loft conversions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.
| Dormer loft conversions | Guide price incl. VAT |
|---|---|
| Rear dormer, bedroom only | £50,000 to £65,000 |
| Full-width dormer with en-suite | £60,000 to £80,000 |
| L-shaped dormer (over rear outrigger) | £65,000 to £90,000 |
Do you need permission for a dormer loft conversion in Cardiff?
Welsh projects need planning clearance from the council under Welsh rules, building regulations approval under the Welsh approved documents, and party wall notices where the work affects a neighbour’s wall or foundations.
Wales has its own loft and roof permitted development rules.
What can affect a dormer loft conversion?
- Dormer cheeks close to a shared wall can trigger the Party Wall Act.
- A flat dormer roof needs proper falls and a quality membrane.
What are the steps?
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
What people ask before starting
How long does a dormer conversion take?
Around 8 to 12 weeks on site.
Can a dormer include a bathroom?
Yes. The full head height in a dormer makes it the best place for a shower room or en-suite.
How do I get a price for dormer loft conversions in Cardiff?
Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.
Also covering
- Dormer loft conversions in Whitchurch
- Dormer loft conversions in Penarth
- Dormer loft conversions in Caerphilly
- Dormer loft conversions in Barry
Learn more about dormer loft conversions, or see every project we cover in Cardiff.