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 Stratford-upon-Avon?
In Stratford-upon-Avon, a dormer loft conversion typically costs £46,500–£66,000 for a typical rear dormer with en-suite, including VAT at 20% (standard rate). Prices in the West Midlands sit near the national average for this kind of work, and the range for Stratford-upon-Avon reflects that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical rear dormer with en-suite | £46,500–£66,000 |
| Higher specification | £66,000–£82,500 |
The main things that change the cost:
- Fire safety upgrades to the existing house
- Dormer size and roof structure
- Scaffolding and access
- Built-in storage and finishes
Use the guide price tool to see how size and specification change the figure, then ask for a written, itemised quote.
Do you need planning permission for a dormer loft conversion in Stratford-upon-Avon?
Whether you need planning permission depends on your house and its location in England. In England a rear dormer is often permitted development if the extra roof volume is no more than 40 cubic metres on a terraced house or 50 on other houses, it does not face the road, sits no higher than the ridge and is set back from the eaves, with matching materials and obscure-glazed side windows. Balconies, front dormers and work in conservation areas need planning permission.
Where work involves a shared wall, building on the boundary, or digging foundations within 3 metres of a neighbour’s building and deeper than its foundations (or within 6 metres for deeper work), the Party Wall etc. Act 1996 applies and notices must be served before work starts.
We check this for your address before design work starts, so there are no surprises later.
What we handle
What we take care of:
- Party wall notices for shared walls
- Measured survey and head-height check
- Dormer structure, roof covering and windows
- Building control completion certificate
- Steel beams and new floor joists
- Insulation, plastering, electrics and plumbing
How long does it take?
Build time is typically 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 Stratford-upon-Avon
Across the West Midlands, inter-war and post-war semis make up much of the housing, giving good scope for two-storey side extensions and hip-to-gable lofts.
Our Stratford-upon-Avon coverage includes postcode districts CV37, and we also work in nearby places such as Warwick, Leamington Spa and Kenilworth.
How it works
- 01
Visit and measured survey
A free visit to understand the project, check access and take measurements.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals
Planning or permitted development confirmation, building regulations and any party wall matters.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about dormer loft conversions in Stratford-upon-Avon
How much does a dormer loft conversion cost in Stratford-upon-Avon?
In Stratford-upon-Avon, a dormer loft conversion typically costs £46,500–£66,000 for a typical rear dormer with en-suite, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
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.
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.
Do I need a party wall agreement?
In England and Wales, if the conversion cuts into or builds on a shared wall, notices must be served under the Party Wall etc. Act 1996.
Who approves a dormer loft conversion in Stratford-upon-Avon?
Planning matters in Stratford-upon-Avon go to the council covering your address, and the work needs building control approval. We prepare and submit the applications for you.
