Dormer windows in Basildon
From the first measured survey to the completion certificate, we run dormer windows and dormer loft conversions projects in Basildon as a single, managed piece of work.
What we build in Basildon
Because Basildon is largely 1930s semis, post-war estates and weatherboarded and rendered village stock, the roof pitches and span widths we meet are fairly predictable, and that makes feasibility a quick conversation rather than a guess.
Whether that is a single flat roof dormer to make a back bedroom usable, or a full-width rear dormer with a bedroom and en-suite, the process is the same: a free measured survey first, a fixed written price second, and nothing else until you have both in front of you.
Planning permission in Basildon
Whether you need planning permission or a lawful development certificate depends on the elevation, the volume already used and the local authority's Article 4 position — all of which we confirm before design work starts.
Basildon sits in Essex, and local authority interpretation of the volume allowance does vary — which is why we check the planning history at your specific address rather than assuming the neighbours' dormer sets a precedent.
How the job runs
Structure
Ridge beam and floor steels craned or manhandled in, new joists laid, the dormer frame built and sheathed.
Glazing
Windows fitted square, sealed and drained, with escape-compliant opening lights where required.
Survey and feasibility
A specialist measures the roof, checks ridge height, span and structure, and confirms whether you are inside permitted development.
Scaffold and protection
Scaffold designed, erected and inspected. Temporary weather protection over the work area before anything is opened.
We only do dormers. That sounds like a limitation until you have watched a general builder improvise a back gutter on a wet Thursday. The quickest route is a photograph of the rear elevation over WhatsApp — we can usually tell you what is feasible before anyone visits.
Popular in Basildon
Dormer work we are asked for most
Aluminium Dormer Windows
Thermally broken aluminium — the slimmest frames and the largest possible glass area.
Learn moreGRP Fibreglass Dormer Roofing
Seamless glass-reinforced polyester on flat dormer tops — no joints, no seams.
Learn morePitched Roof Dormers
A miniature pitched roof over the dormer — the traditional, period-correct option.
Learn moreFull-Width Rear Dormers
Wall-to-wall across the back of the roof — the biggest gain in usable floor area.
Learn moreCat Slide Dormers
The main roof continues down past the dormer — a soft, cottage-style profile.
Learn moreDormer Window Installation
Supply and fit of the window itself into new or existing dormer openings.
Learn moreFAQs
Dormers in Basildon — FAQs
Do you work on listed buildings and in conservation areas?
Yes. That work is detail-led: matching sightlines, glazing bar widths, cill projections and cheek finishes to what survives, and specifying timber, lead and natural slate rather than modern equivalents. We prepare the drawings and heritage statement for listed building consent alongside the planning application.
What guarantees do you provide?
Structural work carries a ten-year guarantee, GRP and EPDM flat roofing twenty years, windows ten years on frames and sealed units, and lead and zinc work is covered for workmanship for ten years. You also receive the building control completion certificate, which is the document that actually matters when you sell.
Do dormer windows need to be fire escape windows?
In a loft conversion, at least one window in each habitable room generally needs to meet escape requirements — a clear opening of at least 0.33m², minimum 450mm in both height and width, with the bottom of the opening between 800mm and 1100mm above floor level. We specify the opening lights to meet this as standard.
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 much does a dormer window cost?
A single flat roof dormer typically runs from around £9,000 to £20,000 supplied and fitted, depending on width, cladding finish and access. A full-width rear dormer on a semi is usually £28,000 to £45,000, and a complete dormer loft conversion including stairs, insulation, plaster and building control sign-off is more commonly £40,000 to £70,000. Our online guide-price tool gives you an indicative range in about a minute.
Will my roof be open to the weather?
No. The roof is only opened once the scaffold, temporary weather protection and materials are all on site, and the dormer is made weathertight — structure, deck, membrane and temporary glazing — before the crew leaves at the end of the opening-up phase. We do not open a roof on a Friday afternoon.
Find out what your roof will take
A free measured survey in Basildon tells you what is achievable, what it needs, and what it costs — before you commit to anything.