GRP Fibreglass Dormer Roofing in Cornwall
Cornwall homeowners come to us for grp fibreglass dormer roofing that are properly detailed at the junctions — because that is where dormers succeed or fail.
GRP Fibreglass Dormer Roofing — indicative geometry
GRP Fibreglass Dormer Roofing for Cornwall homes
Roofs across Cornwall are dominated by granite and rendered cottages, Victorian villas and post-war bungalows, and that mix decides almost everything about what a dormer here needs to look like and how it has to be built.
GRP is laid wet onto an 18mm OSB or ply deck and cures into one continuous laminate with the trims bonded in — there is no seam, no lap and no weld to fail. On a small flat dormer top with several upstands and a wall abutment, that seamlessness is worth a great deal. It needs dry weather and a temperature above about 5°C to lay properly.
Key specification
| Build-up | 18mm deck, CSM matting, polyester resin, topcoat |
|---|---|
| Trims | GRP edge, drip and wall trims bonded in |
| Design life | 20–25 years |
| Fall | 1:80 minimum |
Planning and building control in Cornwall
If the property is in a conservation area or the dormer faces the road, a full planning application is needed. We prepare the drawings and handle the submission either way.
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 Cornwall use us
Everything is priced from a measured survey, not a phone call — which is why our quotations tend to be the ones that still hold at the end of the job.
The quickest route is a photograph of the rear elevation over WhatsApp — we can usually tell you what is feasible before anyone visits.
Other dormer work in Cornwall
FAQs
GRP Fibreglass Dormer Roofing in Cornwall — FAQs
Why is my dormer leaking?
In our experience the window itself is the cause less than a fifth of the time. Far more often it is the apron flashing at the dormer front, the lead soakers where the cheeks meet the roof slope, the back gutter behind a pitched dormer, or a split at an upstand in the flat covering. Water then tracks along a rafter and appears somewhere else entirely, which is why we trace the path before quoting.
Will a dormer add value to my house?
A properly built and signed-off dormer conversion adding a bedroom and bathroom typically returns a meaningful share of its cost in value, and more in areas where floor space is scarce. The building control completion certificate is what makes the space count as habitable floor area on a valuation — without it, surveyors will not include it.
Is scaffolding included in the price?
Yes. Every quotation we issue includes scaffold design, erection, weekly inspection, hire for the programme and dismantling. Scaffold appearing as an extra afterwards is one of the more common complaints about dormer work, so we price it in from the start.
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.
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.
Find out what your roof will take
A free measured survey in Cornwall tells you what is achievable, what it needs, and what it costs — before you commit to anything.