Dormer windows in Coleford
Coleford homeowners come to us for dormer windows and dormer loft conversions that are properly detailed at the junctions — because that is where dormers succeed or fail.
What we build in Coleford
Coleford is a mix of Victorian and Edwardian terraces, interwar semi-detached houses and post-war bungalows, and each of those wants a different dormer form — which is why we survey before quoting rather than pricing off a photograph.
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 Coleford
Rear dormers on houses often sit inside permitted development, but the volume allowance is consumed by any previous loft or rear extension — so we check the planning history for the address before we say yes.
Coleford sits in Gloucestershire, 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
Design and consent
Measured drawings, elevations and sections. We submit the planning application or lawful development certificate and the building regulations application.
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.
One quotation covers scaffold, structure, weatherproofing, glazing, plastering and sign-off. You are not coordinating four trades who each blame the last one. Book the survey, get the fixed written price, and decide in your own time. Nothing about that process commits you to anything.
Popular in Coleford
Dormer work we are asked for most
Conservation Dormer Windows
Heritage-profile dormers and glazing for conservation areas and listed buildings.
Learn moreDormer Window Repairs
Leaks, rot, failed flashings, blown units and draughts — diagnosed and put right.
Learn moreHipped Roof Dormers
Three sloping faces instead of a gable — softer, and often easier to get past planning.
Learn moreBox Dormers
A simple squared projection — the workhorse dormer for bedrooms and bathrooms.
Learn moreBungalow Dormer Conversions
Turn a bungalow's roof void into a first floor — often doubling the footprint.
Learn moreuPVC Dormer Windows
Low maintenance, well insulated and the most cost-effective frame for a dormer.
Learn moreFAQs
Dormers in Coleford — FAQs
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.
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.
Find out what your roof will take
A free measured survey in Coleford tells you what is achievable, what it needs, and what it costs — before you commit to anything.