Covering Basingstoke
We work in Basingstoke (RG21) and the places around it, including Fleet, Thatcham and Farnham.
Homes in the South East
Many South East homes are inter-war or post-war semis and detached houses with room for rear and side extensions, while historic town centres and villages bring conservation area and listed building controls.
What does a dormer loft conversion involve?
A dormer loft conversion builds a box-shaped extension out from the rear slope of the roof, creating vertical walls and full head height across most of the new floor. It is the most popular type of loft conversion because it gives the most usable space for the cost.
- Volume calculation and permitted development check
- Lawful development certificate or planning drawings
- Steelwork and new floor structure
What will a dormer loft conversion cost?
Use these ranges to budget for dormer loft conversions; the survey turns them into a fixed price for the agreed specification.
| Dormer loft conversions | Guide price incl. VAT |
|---|---|
| Rear dormer, bedroom only | £50,000 to £65,000 |
| Full-width dormer with en-suite | £60,000 to £80,000 |
| L-shaped dormer (over rear outrigger) | £65,000 to £90,000 |
What approvals does a dormer loft conversion need in England?
English projects need planning clearance from the local council, building regulations sign-off from building control, and party wall notices where the work is on or near a shared boundary. We prepare and manage all three.
In England many loft conversions are permitted development: the extra roof volume must stay within 40 m³ on a terraced house or 50 m³ on a semi or detached house, nothing can sit higher than the existing ridge, no dormer can face a road on the main elevation, and side windows must be obscure-glazed and non-opening below 1.7 m.
What should Basingstoke homeowners check first?
- Dormers on the front of the house facing a road are not permitted development in England.
- A flat dormer roof needs proper falls and a quality membrane.
What are the steps?
- Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
- Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
- Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
Your questions answered
How long does a dormer conversion take?
Around 8 to 12 weeks on site.
What cladding can a dormer have?
Tile-hanging to match the roof, render, slate, timber or zinc, depending on the house and any planning conditions.
How do I get a price for dormer loft conversions in Basingstoke?
Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.
Also covering
- Dormer loft conversions in Fleet
- Dormer loft conversions in Thatcham
- Dormer loft conversions in Farnham
- Dormer loft conversions in Aldershot
Learn more about dormer loft conversions, or see every project we cover in Basingstoke.

