Covering Abergavenny
We work in Abergavenny (NP7) and the places around it, including Pontypool, Ebbw Vale and Cwmbran.
Homes in Gwent
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 mansard loft conversion?
Mansards are a bigger structural job than other conversions because the roof is largely rebuilt. They normally need planning permission, and many councils have design guides setting the angle, materials and window style. We prepare the design to those guides and build in slate, lead and timber or approved alternatives.
- Structural design and party wall process
- Slate cladding and lead-clad dormers
- En-suite, electrics and fire safety
How much should I budget for a mansard loft conversion?
Typical ranges for mansard loft conversions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.
| Mansard loft conversions | Guide price incl. VAT |
|---|---|
| Rear mansard | £65,000 to £85,000 |
| Front and rear (double) mansard | £80,000 to £110,000 |
What approvals does a mansard loft conversion need in Wales?
In Wales the planning rules, including what counts as permitted development, are set by the Welsh Government, and Welsh building regulations differ in places from England’s. We check both against your house before drawings are finalised, and handle party wall notices where needed.
This needs full planning permission from your council in Wales. We prepare and submit the application and deal with the planning officer on your behalf.
What can affect a mansard loft conversion?
- A mansard nearly always involves party walls on both sides of a terrace.
- The roof is open for longer than with a dormer, so weather protection matters.
How does the project run?
- 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.
- Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
What people ask before starting
How much does a mansard loft conversion cost?
Typically £65,000 to £110,000 including VAT, depending on whether one or both roof slopes are rebuilt.
Does a mansard need planning permission?
Almost always, because it changes the roof profile.
How do I get a price for mansard loft conversions in Abergavenny?
Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.
Other towns nearby
- Mansard loft conversions in Pontypool
- Mansard loft conversions in Ebbw Vale
- Mansard loft conversions in Cwmbran
- Mansard loft conversions in Monmouth
Learn more about mansard loft conversions, or see every project we cover in Abergavenny.

