Dormer windows in Chepstow
We design, build and weatherproof dormer windows and dormer loft conversions for homeowners across Chepstow, working from first survey through to building control sign-off.
What we build in Chepstow
Chepstow 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 Chepstow
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.
Chepstow sits in Monmouthshire and Newport, 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
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.
Weatherproofing
Deck, insulation, membrane or lead, cheek cladding, flashings and gutters — the dormer is weathertight from this point.
One quotation covers scaffold, structure, weatherproofing, glazing, plastering and sign-off. You are not coordinating four trades who each blame the last one. If you want to know what your roof will actually take, the survey is free and there is no obligation attached to it.
Popular in Chepstow
Dormer work we are asked for most
Velux to Dormer Conversions
Already have rooflights? Convert the slope to a dormer and gain standing height.
Learn moreTimber Dormer Windows
Engineered hardwood or softwood — the right answer on period and listed roofs.
Learn moreDormer Cladding
Re-clad tired dormer cheeks and faces in tile, lead, zinc, timber or GRP.
Learn moreFlat Roof Dormers
The most space-efficient dormer — a flat-topped box that squares off the roof slope.
Learn moreShed Dormers
A single shallow slope running with the main roof — wide, low and understated.
Learn moreEyebrow Dormers
A curved, brow-like swell in the roof — no cheeks, no vertical faces.
Learn moreFAQs
Dormers in Chepstow — FAQs
Can you match my existing roof tiles?
Usually. Most common clay and concrete profiles are still in production or available reclaimed, and we source a match at survey stage so you see it before work starts. Where a discontinued profile cannot be matched exactly, we normally recommend taking tiles from a less visible slope for the dormer and using the closest new match on the hidden elevation.
What is the difference between a dormer and a Velux?
A rooflight sits flush in the roof slope and gives you light without any extra height — you still have a sloping ceiling. A dormer projects out from the roof and creates vertical walls with a level ceiling behind them, so you gain genuinely usable standing space and floor area, not just daylight.
How wide can a dormer be?
Structurally, as wide as the roof — full-width rear dormers regularly run six to eight metres, carried on a steel ridge beam. The limits are usually planning volume allowances and the setbacks needed at eaves and ridge, rather than what can be built.
How disruptive is a dormer build?
Less than people expect, because most of the work happens above your ceilings and is reached from the scaffold. The noisy phases are opening up and installing steels, typically two to four days. Once the staircase is cut in there is dust and traffic through the house, and we sheet and protect the route for that period.
Can a dormer include an en-suite?
Very often, yes — a full-width or L-shaped dormer usually has enough floor area for a bedroom plus a shower room. The practical constraints are getting soil and waste down to an existing stack, and whether the head height over the shower tray works. Both are settled at survey.
Can you build a dormer in winter?
Yes, with adjustments. Temporary weather protection over the scaffold lets structural work continue in most conditions. GRP roofing needs dry conditions above about 5°C to cure properly, so in a cold spell we either sequence it differently or specify EPDM, which is unaffected.
Find out what your roof will take
A free measured survey in Chepstow tells you what is achievable, what it needs, and what it costs — before you commit to anything.