EPDM rubber, GRP fibreglass, roof lanterns
Flat roofs
Extension, garage, porch and dormer roofs in EPDM rubber or GRP fibreglass, laid on new decking where the old one is soft, with a twenty-year guarantee and no felt in sight.
Felt flat roofs last fifteen years if you are lucky. A single-sheet EPDM or a GRP roof lasts forty, has no seams to fail, and we guarantee it for twenty.
EPDM is a single rubber membrane cut to the roof in one piece, so there are no joins on the roof itself, bonded to the deck and dressed up the walls and into the gutter with proper trims. It takes a day on most extensions and the roof can be walked on. GRP is a fibreglass laminate laid wet and topped with a coloured coat; it is harder, suits roofs with lots of detail and is the better choice for balconies and walk-on roofs.
Both need a dry, flat deck. We lift the old felt, check the boards, and replace anything soft. If the roof needs insulating to meet building regulations (it does when more than half the covering is replaced) we fit a warm-roof build-up with insulation above the deck, which also cures the condensation that rots old flat roofs from below.
Roof lanterns and skylights are fitted at the same time, with the upstands formed in the membrane so they do not leak at the corners, which is where every lantern leak starts.
What is included
- Old felt stripped and deck inspected
- New OSB or plywood decking where the old is soft
- Warm-roof insulation where regulations require it
- EPDM in one sheet or GRP with a coloured topcoat
- Lanterns, skylights, outlets and trims
- Twenty-year insurance-backed guarantee
What it costs
EPDM flat roofs from £1,900 for a single garage, £3,400 for a typical extension including new decking and insulation where needed. GRP from £2,300. All prices include scaffold or access, waste removal and VAT. See the full price list.
Questions about flat roofs
EPDM or GRP?
EPDM for most extensions and garages: faster, cheaper, flexible, no joins. GRP for walk-on roofs, balconies, roofs with lots of upstands and detail, and anywhere you want a colour other than black.
Can you fix a leaking felt roof instead of replacing it?
Sometimes, for a year or two. Felt fails everywhere at once, so a patch tends to be followed by another. We will tell you if a patch is worth it; often the honest answer is no.
Get the roof looked at properly.
A free drone survey, a photo report you keep, and a fixed quote that includes the scaffold and the skip. Storm damage: ring the storm line, any hour.