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 Stretford?
In Stretford, a dormer loft conversion typically costs £45,000–£64,000 for a typical rear dormer with en-suite, including VAT at 20% (standard rate). Prices across the North West are typically 6% below the UK average for this kind of work, which is reflected in the range for Stretford. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical rear dormer with en-suite | £45,000–£64,000 |
| Higher specification | £64,000–£80,000 |
What moves the price most:
- Fire safety upgrades to the existing house
- Built-in storage and finishes
- Dormer size and roof structure
- En-suite or bathroom
For a figure based on your own measurements, try the guide price tool, then book a free home visit for a fixed quote.
Do you need planning permission for a dormer loft conversion in Stretford?
Approvals for a dormer loft conversion in Stretford follow the rules for 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.
Building regulations approval comes from the council’s building control service or a registered building control approver. The work is inspected at key stages, such as foundations, drainage and insulation, and a completion certificate is issued at the end.
If the answer is not clear-cut, we can apply for formal confirmation before you commit to the build.
What we handle
On a typical dormer loft conversion we handle:
- Steel beams and new floor joists
- Party wall notices for shared walls
- Measured survey and head-height check
- Building control completion certificate
- Dormer structure, roof covering and windows
- New staircase and fire-safe escape route
How long does it take?
Allow 6 to 9 weeks on site. Allow time beforehand for drawings and approvals, usually 6 to 12 weeks.
Building in Stretford
The North West has many brick terraces and inter-war semis, where kitchen extensions and dormer loft conversions add space without moving.
From M32 outwards, we take on projects throughout Stretford and the surrounding parts of Greater Manchester.
How it works
- 01
Survey and brief
We visit, discuss your ideas and budget, and survey the property or site at no cost.
- 02
Design and pricing
Design options, then a fixed quote based on the chosen drawings and specification.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about dormer loft conversions in Stretford
Do you build dormer loft conversions in Stretford?
Yes. We build dormer loft conversions across Stretford, including postcodes M32. Every project starts with a free home visit.
How much head height do I need?
Ideally at least 2.2 metres from the top of the ceiling joists to the underside of the ridge. Less can still work with a dormer, but we check this at the survey.
How much does a dormer loft conversion cost in Stretford?
In Stretford, a dormer loft conversion typically costs £45,000–£64,000 for a typical rear dormer with en-suite, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
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.
Does a dormer loft conversion need planning permission?
A rear dormer is often permitted development in England, provided the extra roof volume is within 40 cubic metres on a terraced house or 50 on a semi-detached or detached house, and it does not face the road. Front dormers and houses in conservation areas usually need an application.
