Flat Roofing in Torbay and South Devon

Flat roofs get a bad name because so many of them were laid badly, and because the failure is slow and hidden. A felt roof over a kitchen extension can look tired but tolerable from the bedroom window for years while the deck underneath goes soft, the insulation fills with water and the plasterboard ceiling below starts to sag. By the time there is a drip, the timber has been wet for a long time. So when we look at a flat roof we walk it, we press it, and we look at the edges and the outlets where the water is supposed to leave. If the deck is sound and the covering is the only problem, a new covering is a straightforward job. If the deck has gone, the honest answer is to take the roof off and start again: new joists where they are needed, insulation between or above them so the room below stops losing heat through its lid, a new OSB3 deck screwed down flat and to a fall, and then the covering. Which covering depends on the roof. Torch-on felt is proven and good for larger roofs with detail. GRP fibreglass is laid wet in one piece with no joints and is hard-wearing on smaller roofs and dormers. EPDM rubber is a single sheet with no seams to fail and is what we reach for on a simple rectangle. The flat-roof job photographed on this page shows the whole thing from a rotten deck to a finished roof, because that is what a flat roof done properly looks like underneath.

See the flat-roof job from rotten deck to finished

• A pond that is still there an hour after the rain has stopped
• Blisters, bubbles or cracks in the felt, or laps that have opened
• Moss and lichen across the surface, or sand washing off into the gutter
• A soft or springy spot when someone walks on it
• A ceiling below that has sagged, stained or grown mould in a corner
• Water running down the wall below the edge trim instead of into the gutter

Flat roof letting water in? Send a photo.