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 Hailsham?
In Hailsham, a dormer loft conversion typically costs £54,000–£76,000 for a typical rear dormer with en-suite, including VAT at 20% (standard rate). We start from a UK-wide guide and adjust it for the South East, where labour and materials are typically about 12% above average. Design, structural calculations and council fees are extra.
| Size or type | Guide range |
|---|---|
| A typical rear dormer with en-suite | £54,000–£76,000 |
| Higher specification | £76,000–£95,000 |
What moves the price most:
- Scaffolding and access
- Staircase position
- Fire safety upgrades to the existing house
- 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 Hailsham?
Approvals for a dormer loft conversion in Hailsham 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
What we take care of:
- Dormer structure, roof covering and windows
- Steel beams and new floor joists
- Party wall notices for shared walls
- Building control completion certificate
- Measured survey and head-height check
- Drawings and structural calculations
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 Hailsham
The South East has a broad mix of housing, from Victorian terraces in the towns to post-war semis and newer estates, so extension types vary street by street.
If your home is in Hailsham or close by in Eastbourne, Seaford and Bexhill-on-Sea, a free home visit is the first step.
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 handover
Work follows the agreed programme, with inspections along the way and a completion certificate at the end.
Questions about dormer loft conversions in Hailsham
How long does it take?
Usually 6 to 9 weeks on site.
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 much does a dormer loft conversion cost in Hailsham?
In Hailsham, a dormer loft conversion typically costs £54,000–£76,000 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.
Do you build dormer loft conversions in Hailsham?
Yes. We build dormer loft conversions across Hailsham, including postcodes BN27. Every project starts with a free home visit.