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 Grays?
In Grays, a dormer loft conversion typically costs £51,000–£72,000 for a typical rear dormer with en-suite, including VAT at 20% (standard rate). Building costs in the East of England run about 6% above the UK average, and the figures for Grays 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 | £51,000–£72,000 |
| Higher specification | £72,000–£90,000 |
Your quote will depend mainly on:
- Fire safety upgrades to the existing house
- Built-in storage and finishes
- Scaffolding and access
- 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 Grays?
The approval route for Grays is set by planning law 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
The work we manage on a dormer loft conversion:
- Dormer structure, roof covering and windows
- Building control completion certificate
- Steel beams and new floor joists
- Party wall notices for shared walls
- Insulation, plastering, electrics and plumbing
- Drawings and structural calculations
How long does it take?
Build time is typically 6 to 9 weeks on site. Allow time beforehand for drawings and approvals, usually 6 to 12 weeks.
Building in Grays
Across the East of England, 1930s and post-war semis, newer estates and rural cottages all feature, each with different extension and loft options.
If your home is in Grays or close by in South Ockendon, Gravesend and Dartford, a free home visit is the first step.
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
Permissions sorted
Applications, building control and neighbour arrangements, all before the start date.
- 04
Construction and completion
We build, put right any snags and hand over the building control certificate.
Questions about dormer loft conversions in Grays
How much does a dormer loft conversion cost in Grays?
In Grays, a dormer loft conversion typically costs £51,000–£72,000 for a typical rear dormer with en-suite, including VAT at 20% (standard rate). Your fixed price depends on the survey and drawings.
Do you build dormer loft conversions in Grays?
Yes. We build dormer loft conversions across Grays, including postcodes RM17. 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.
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.