Flat Roofing

Choosing a flat roofing system

There's no single best system — there's the right one for the roof in question. Modern torch-on felt remains a sound, economical choice on garages and outbuildings. EPDM rubber comes in one seamless sheet, which makes it excellent on simple rectangles like garage and extension roofs — no joints, nothing to lift. GRP fibreglass is laid wet and cures into a single rigid skin, which suits complicated shapes, walkways and balconies where a membrane would need too many joints.

Why flat roofs fail

Almost always at the edges and details, not in the middle: ponding where the falls were never right, splits at upstands and trims, and joints that give up before the field of the roof does. Age plays its part — old mineral felt embrittles and cracks — but poor detailing is the biggest killer, which is why our flat roof repair work starts with working out whether the covering is worth repairing at all.

Repair or replace?

A local split or a failed joint on an otherwise sound covering is repairable. A felt roof that's blistered and crazed across its area, or one that ponds because the deck beneath has sagged, is telling you it's done — and money spent patching is money towards nothing. Because flat roofs are smaller than main roofs, replacement is often less than people fear; we'll price both options where both are viable.

If your flat roof is on an extension or garage you're re-thinking anyway, see our extension, garage & porch roofs page — sometimes the right answer is a warm-deck rebuild rather than another covering on a cold, tired deck.