Dormer loft conversions in Bexley

Covering Bexley

We work in Bexley (DA15) and the places around it, including Welling, Dartford and Swanley.

Homes in London

London projects often mean working on period terraces with neighbours on both sides, tight access through the house and conservation area controls, so careful planning and party wall work matter as much as the build.

What do you get with a dormer loft conversion?

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
En-suite, electrics and fire-protected escape route

How much should I budget for a dormer loft conversion?

Indicative costs for dormer loft conversions. London and the South East usually sit towards the top of each range.

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

How is a dormer loft conversion approved in Bexley?

In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it 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.
A flat dormer roof needs proper falls and a quality membrane.

From first call to completion

Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.

Dormer loft conversions: common questions

How long does a dormer conversion take?

Around 8 to 12 weeks on site.

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.

Do you work in Bexley?

Yes. Bexley is within our coverage for dormer loft conversions, along with nearby Welling and Dartford.

Other towns nearby

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