Dormer loft conversions in Welling

Covering Welling

We work in Welling (DA16) and the places around it, including Bexley, Eltham and Thamesmead.

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 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?

Typical ranges for dormer loft conversions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.

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

Planning and building rules in Welling

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 I think about before starting?

Dormer cheeks close to a shared wall can trigger the Party Wall Act.
A flat dormer roof needs proper falls and a quality membrane.

How does the project run?

Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.

Your questions answered

How much does a dormer loft conversion cost?

Typically £50,000 to £80,000 including VAT, and up to around £90,000 for an L-shaped dormer.

How long does a dormer conversion take?

Around 8 to 12 weeks on site.

Do you work in Welling?

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

Dormer loft conversions near Welling

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