Shed Dormers in Conwy
We design, build and weatherproof shed dormers for homeowners across Conwy, working from first survey through to building control sign-off.
Shed Dormers — indicative geometry
Shed Dormers for Conwy homes
Because Conwy is largely Victorian and Edwardian terraces, interwar semi-detached houses and post-war bungalows, the roof pitches and span widths we meet are fairly predictable, and that makes feasibility a quick conversation rather than a guess.
A shed dormer has one plane, pitched more shallowly than the main roof, running back to meet it. Because there are no hips or valleys it is the cheapest wide dormer to build, and it can stretch across most of a rear elevation without looking like a bolted-on box. It suits 1930s semis and chalet bungalows particularly well.
Key specification
| Typical projection | 2.4m – 7.0m wide |
|---|---|
| Pitch | 15° – 25°, shallower than main roof |
| Roof finish | Interlocking tile, slate or membrane |
| Structure | Rafters spanning to a ridge beam |
Planning and building control in Conwy
Getting the consent route right at the start saves months. We establish whether it is permitted development, a lawful development certificate or a full application on the first visit.
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
The completion certificate is part of the deliverable, not an afterthought. It is the document that makes the space count when you come to sell.
If you want to know what your roof will actually take, the survey is free and there is no obligation attached to it.
Other dormer work in Conwy
FAQs
Shed Dormers in Conwy — FAQs
What is the best roof covering for a flat dormer?
GRP fibreglass and EPDM rubber are the two we specify most. GRP cures into a single seamless laminate with bonded trims and suits small tops with several upstands. EPDM is a one-piece membrane that copes better with movement on larger spans. Both carry twenty-year guarantees; mineral felt is cheaper but has a materially shorter life.
What insulation do dormers need?
Current building regulations want around 0.15–0.18 W/m²K for a new dormer roof and 0.18 W/m²K for the cheeks and front. In practice that is a warm-roof build-up using 100–150mm of PIR insulation above or between the structure, with a continuous vapour control layer on the warm side. Getting the VCL continuous matters more than the insulation thickness.
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.
Can you convert an existing Velux loft to a dormer?
Yes, and it is usually a shorter job than starting from scratch because the floor, staircase and services already exist. We verify the existing floor structure and any previous building control approval first, then cut and form the dormer into the finished room. Expect the room to be out of use for three to five weeks.
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.
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.