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 Clydach?
In Clydach, a dormer loft conversion typically costs £44,000–£62,500 for a typical rear dormer with en-suite, including VAT at 20% (standard rate). Building costs in Wales run about 8% below the UK average, and the figures for Clydach are adjusted to reflect that. 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 |
The biggest cost drivers are:
- Dormer size and roof structure
- Fire safety upgrades to the existing house
- En-suite or bathroom
- Staircase position
Your exact price depends on the survey and drawings. The guide price tool gives a quick range in the meantime.
Do you need planning permission for a dormer loft conversion in Clydach?
Before anything is built in Clydach, we confirm which approvals apply 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.
At the survey we check your house’s planning history and any restrictions, and tell you which route applies.
What we handle
Handled as part of most dormer loft conversions:
- Steel beams and new floor joists
- Party wall notices for shared walls
- Building control completion certificate
- Dormer structure, roof covering and windows
- Measured survey and head-height check
- Insulation, plastering, electrics and plumbing
How long does it take?
The build itself usually takes 6 to 9 weeks on site. Design and approvals come first and typically take 6 to 12 weeks, depending on the approval route.
Building in Clydach
Terraced houses in Welsh towns often have narrow plots, which suits rear and side return extensions and rear dormers.
Our Clydach coverage includes postcode districts SA6, and we also work in nearby places such as Neath, Swansea and Gorseinon.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Drawings and written quote
We prepare the design and give you a written, itemised quote with inclusions and exclusions.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 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 Clydach
How much does a dormer loft conversion cost in Clydach?
In Clydach, 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.
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.
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.
Do I need planning permission for a dormer loft conversion in Clydach?
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.
Do you build dormer loft conversions in Clydach?
Yes. We build dormer loft conversions across Clydach, including postcodes SA6. Every project starts with a free home visit.
How long does it take?
Usually 6 to 9 weeks on site.