Dormer loft conversions in Southampton

Covering Southampton

We work in Southampton (SO15) and the places around it, including Totton, Eastleigh and Fareham.

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 is included in a dormer loft conversion in Southampton?

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.

Steelwork and new floor structure
Staircase, insulation and plasterboard
En-suite, electrics and fire-protected escape route

What will a dormer loft conversion cost?

What dormer loft conversions typically cost. These are guide ranges; the written quote for your house replaces them.

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?

Projects in England go through two separate checks. Planning (or confirmation that the work is permitted development) comes from the district, borough or unitary council, and building regulations approval comes from the council’s building control team or a registered building control approver. Where work touches a shared wall or digs near a neighbour’s foundations, the Party Wall etc. Act 1996 applies.

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. Houses in conservation areas, National Parks and National Landscapes cannot use these roof-extension rights, so dormers there need planning permission (a rooflight-only conversion can still be permitted development), and flats always need permission.

What should I think about before starting?

Dormers on the front of the house facing a road are not permitted development in England.
L-shaped dormers are common on Victorian terraces with a rear outrigger.

From first call to completion

Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
Construction and completion. One site lead co-ordinates every trade through to the building control certificate.

Your questions answered

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.

Can a dormer include a bathroom?

Yes. The full head height in a dormer makes it the best place for a shower room or en-suite.

Can you visit a house in Southampton to quote?

Yes. After a short call we arrange a site visit to measure up and agree what the design needs to do, then send a written price.

Dormer loft conversions near Southampton

Learn more about dormer loft conversions, or see every project we cover in Southampton.