What is a dormer loft conversion?

A dormer loft conversion adds a box-shaped structure to the rear roof slope, creating vertical walls and full headroom across most of the new room. It is the most common loft conversion in the UK because it works on terraced, semi-detached and detached houses.
How much does a dormer loft conversion cost in Welshpool?
In Welshpool, a dormer loft conversion typically costs £44,000–£62,500 for a typical rear dormer with en-suite, 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 typical rear dormer with en-suite | £44,000–£62,500 |
| Higher specification | £62,500–£78,000 |
Your quote will depend mainly on:
- Fire safety upgrades to the existing house
- En-suite or bathroom
- Dormer size and roof structure
- Staircase position
A guide range is only a starting point: the guide price tool gives an instant figure for your size, and a free survey turns it into a fixed quote.
Do you need planning permission for a dormer loft conversion in Welshpool?
The approval route for Welshpool is set by planning law in Wales. In Wales roof enlargements such as rear dormers can be permitted development within volume limits and design conditions. Dormers facing a road, balconies and conservation-area work 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
What we take care of:
- Insulation, plastering, electrics and plumbing
- Party wall notices for shared walls
- Measured survey and head-height check
- Building control completion certificate
- Dormer structure, roof covering and windows
- Steel beams and new floor joists
How long does it take?
Build time is typically 6 to 9 weeks on site. Before that, surveys, drawings and approvals usually take 6 to 12 weeks, longer if the council asks for changes.
Building in Welshpool
Terraced houses in Welsh towns often have narrow plots, which suits rear and side return extensions and rear dormers.
We work across Welshpool and neighbouring areas such as Newtown, Wrexham and Llandrindod Wells. Postcodes we cover in Welshpool include SY21.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Build and handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about dormer loft conversions in Welshpool
Do I need planning permission for a dormer loft conversion in Welshpool?
In Wales roof enlargements such as rear dormers can be permitted development within volume limits and design conditions. Dormers facing a road, balconies and conservation-area work need permission.
What fire safety is required?
Building regulations require a safe escape route. Converting a two-storey house to three storeys usually means a protected stairway with fire doors to habitable rooms and mains-wired smoke alarms.
How long does it take?
Usually 6 to 9 weeks on site.
How much does a dormer loft conversion cost in Welshpool?
In Welshpool, a dormer loft conversion typically costs £44,000–£62,500 for a typical rear dormer with en-suite, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Do you build dormer loft conversions in Welshpool?
Yes. We build dormer loft conversions across Welshpool, including postcodes SY21. Every project starts with a free home visit.
Will I need to move out?
No. Most of the work is done from scaffolding and the roof. The new staircase is formed near the end, which causes a few days of disruption.
