Covering Caernarfon
We work in Caernarfon (LL55) and the places around it, including Llangefni, Bangor and Pwllheli.
Homes in Gwynedd and Anglesey
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 a dormer loft conversion?
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
- Steelwork and new floor structure
- Dormer frame, roof covering and cladding
How much does a dormer loft conversion cost in Caernarfon?
Guide prices for dormer loft conversions, including VAT where it applies. Your fixed price is confirmed in writing after the survey.
| 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 |
How is a dormer loft conversion approved in Caernarfon?
Planning decisions in Wales are made by the local council, using permitted development rules set by the Welsh Government rather than England’s. Building regulations in Wales have their own approved documents, and the Party Wall etc. Act 1996 applies to work on shared walls and boundaries.
Wales has its own loft and roof permitted development rules.
What should I think about before starting?
- Dormer cheeks close to a shared wall can trigger the Party Wall Act.
- L-shaped dormers are common on Victorian terraces with a rear outrigger.
From first call to completion
- Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
- Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
Your questions answered
How much does a dormer loft conversion cost?
Typically £50,000 to £80,000 including VAT, and up to around £90,000 for an L-shaped dormer.
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.
Do you work in Caernarfon?
Yes. Caernarfon is within our coverage for dormer loft conversions, along with nearby Llangefni and Bangor.
Dormer loft conversions in nearby towns
- Dormer loft conversions in Llangefni
- Dormer loft conversions in Bangor
- Dormer loft conversions in Pwllheli
- Dormer loft conversions in Holyhead
Learn more about dormer loft conversions, or see every project we cover in Caernarfon.