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Dormer Loft Conversions in West Sussex

From the first measured survey to the completion certificate, we run dormer loft conversions projects in West Sussex as a single, managed piece of work.

Free measured surveyA specialist visits, measures and tells you what the roof will and will not take.
Fixed written priceOne quotation covering structure, scaffold, weatherproofing, glazing and making good.
Building control managedWe submit, book the inspections and hand you the completion certificate.
Insured and guaranteed£5m public liability, ten-year structural and twenty-year flat roofing guarantees.
Nationwide coverageDirectly employed and vetted specialist teams across England, Wales, Scotland and Northern Ireland.

Dormer Loft Conversions — indicative geometry

Dormer Loft Conversions for West Sussex homes

Roofs across West Sussex are dominated by Victorian and Edwardian terraces, interwar semi-detached houses and post-war bungalows, and that mix decides almost everything about what a dormer here needs to look like and how it has to be built.

A dormer loft conversion is the whole sequence: steels and a new floor structure, the dormer itself, a compliant staircase, fire-rated doors and a protected escape route, insulation to current Part L, electrics, heating and plaster. Building control sign-off is what turns loft space into habitable floor area on a survey and on a mortgage valuation — and it is the part people skip at their peril.

Key specification

Floor area gained15m² – 30m² typical
Head height required2.2m+ over the stair landing
StructureFloor steels, ridge beam, new joists
CompliancePart L, Part B fire, Part K stairs
Indicative guide prices. Our online tool gives a realistic range in about a minute — pick your dormer type, width, finish and scope. Get an indicative price →

Planning and building control in West Sussex

If the property is in a conservation area or the dormer faces the road, a full planning application is needed. We prepare the drawings and handle the submission either way.

Building regulations approval is separate and always required. We submit the application, book the inspections around the programme and hand you the completion certificate at the end — the document a buyer's surveyor will ask to see.

Why homeowners in West Sussex use us

Everything is priced from a measured survey, not a phone call — which is why our quotations tend to be the ones that still hold at the end of the job.

The quickest route is a photograph of the rear elevation over WhatsApp — we can usually tell you what is feasible before anyone visits.

Other dormer work in West Sussex

FAQs

Dormer Loft Conversions in West Sussex — FAQs

What happens to my existing loft insulation?

It comes out. Insulation at ceiling-joist level is in the wrong place once the loft is a room — the thermal line moves up to the new roof and dormer build-up. We remove and dispose of the old quilt and insulate the new envelope, which is also what makes the room comfortable to use in August.

How long does a dormer take to build?

A single box or flat roof dormer is typically three to five weeks on site. A full-width rear dormer runs five to eight weeks, and an L-shaped dormer on a terrace with an outrigger is closer to seven to ten. A complete dormer loft conversion including the staircase, services and finishes is usually eight to twelve weeks from scaffold up to sign-off.

Can you build a dormer on a bungalow?

Usually yes, and bungalows often give the best results because the spans are wide and there are no party walls. The deciding factor is ridge height: you generally want at least 2.6m from the top of the ceiling joists to the underside of the ridge. We measure this at survey before committing to anything.

Can I put a dormer on the front of my house?

Front-facing dormers are not covered by permitted development and always need a full planning application. Approval depends heavily on the street scene — planners look at whether other dormers already exist on the road, and at proportion, position and materials. Hipped and pitched forms are approved far more often than flat boxes on a front elevation.

Do you handle the planning application?

Yes. We prepare measured drawings, elevations and sections, submit the application or the lawful development certificate, and deal with the case officer's queries. On conservation and listed work we also put together the heritage justification the application needs.

Read all frequently asked questions →

Find out what your roof will take

A free measured survey in West Sussex tells you what is achievable, what it needs, and what it costs — before you commit to anything.

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