Flat Roof Dormers in Conwy
Our teams install flat roof dormers throughout Conwy, handling structure, weatherproofing, glazing and finish as one job with one point of contact.
Flat Roof Dormers — indicative geometry
Flat Roof Dormers for Conwy homes
Most of the dormer work we take on around Conwy is on Victorian and Edwardian terraces, interwar semi-detached houses and post-war bungalows, where the ridge height and the position of the existing purlins set the limits.
A flat roof dormer projects square from the roof slope with a shallow-fall flat top, usually finished in GRP fibreglass, EPDM or single-ply membrane. Because the walls are vertical and the ceiling is level, you keep full standing height right up to the window — which is why it is the default choice on rear elevations where planning is under permitted development.
Key specification
| Typical projection | 1.8m – 6.0m wide |
|---|---|
| Roof fall | 1:80 minimum to the rear |
| Roof finish | GRP, EPDM or single-ply membrane |
| Cheek finish | Tile-hung, GRP, lead, zinc or timber |
Planning and building control in Conwy
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.
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 Conwy use us
We would rather tell you at survey that your ridge height will not take what you want than take a deposit and find out in week three.
Send us the address and roughly what you are hoping to gain, and we will come back with a realistic answer rather than an optimistic one.
Other dormer work in Conwy
FAQs
Flat Roof Dormers in Conwy — FAQs
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.
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.
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.
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.
Find out what your roof will take
A free measured survey in Conwy tells you what is achievable, what it needs, and what it costs — before you commit to anything.