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 Gloucester?
In Gloucester, a dormer loft conversion typically costs £49,000–£69,500 for a typical rear dormer with en-suite, including VAT at 20% (standard rate). Prices in the South West sit near the national average for this kind of work, and the range for Gloucester reflects that. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical rear dormer with en-suite | £49,000–£69,500 |
| Higher specification | £69,500–£87,000 |
The main things that change the cost:
- Dormer size and roof structure
- Fire safety upgrades to the existing house
- Staircase position
- Built-in storage and finishes
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 Gloucester?
Here is how the rules work for a dormer loft conversion 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
Handled as part of most dormer loft conversions:
- Dormer structure, roof covering and windows
- Measured survey and head-height check
- Party wall notices for shared walls
- Drawings and structural calculations
- New staircase and fire-safe escape route
- Building control completion certificate
How long does it take?
Expect 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 Gloucester
In parts of the South West, protected landscapes and conservation areas shape what can be built, so materials and roof forms are chosen carefully.
From GL1 outwards, we take on projects throughout Gloucester and the surrounding parts of Gloucestershire.
How it works
- 01
Free visit
We look at the property, talk through what you want and measure up. There is no charge and no obligation.
- 02
Design and fixed quote
Drawings, structural calculations and an itemised, fixed price for the agreed specification.
- 03
Approvals in place
We handle planning, building control and neighbour notices before work starts.
- 04
Build and sign-off
We run the build to a written programme and hand over the completion certificate.
Questions about dormer loft conversions in Gloucester
How long does it take?
Usually 6 to 9 weeks on site.
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.
How much does a dormer loft conversion cost in Gloucester?
In Gloucester, a dormer loft conversion typically costs £49,000–£69,500 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.
Do you build dormer loft conversions in Gloucester?
Yes. We build dormer loft conversions across Gloucester, including postcodes GL1. Every project starts with a free home visit.