Flat roofingand torch-on feltdone to last

The first layer goes down over a prepared deck and controls vapour and movement. The intermediate layer builds thickness and redundancy. The mineral-finished cap sheet takes the UV, the rain and the foot traffic, and is the layer you can see. Each is heat-bonded, with laps run in the direction of the fall so water always crosses a joint the safe way.

Over an unsound deck none of that matters, which is why we check and repair the deck first. New ply, firrings to create or correct the fall, and secure fixing back to the joists all happen before the first roll is unwrapped.

Where a flat roof meets a wall, a dormer cheek or a pitched roof, the covering has to turn up and be terminated properly. Upstands are carried to a sensible height and finished with lead flashing or a proper termination bar rather than a bead of sealant.

Edges get drip trims and welted detail so rainwater is thrown clear into the gutter instead of tracking back under the covering and into the fascia. Outlets and rainwater pipes are dressed into the membrane, not simply bedded against it.

Torch-on suits almost any flat or low-pitch area on domestic and commercial buildings. Some are jobs of a morning; some run for days.

Not every flat roof needs replacing. A localised split, a lifted lap or a failed upstand on an otherwise sound covering can be cut in and repaired, and we will say so rather than sell a whole roof.

Where the mineral finish has weathered away across the roof, blisters have spread, or the deck feels soft underfoot, a re-cover is the honest answer, a repair to a covering that has failed as a whole is money spent twice.

On houses, the flat roof is usually small, closely surrounded by other elements, and sits over a room in daily use. The detailing at the junctions matters more than the area of felt, and access is often through a garden.

Commercial flat roofs are larger, carry plant, vents and service penetrations, and often need to stay in use throughout. Every penetration is a potential leak, so each is detailed individually, and work is phased so no section is left unfinished overnight.

Roofs at Worthing, Shoreham-by-Sea, Littlehampton, Hove and Brighton take salt-laden wind that inland properties never see. Edges and terminations are where that wind does its work, get them wrong and the covering peels rather than leaks.

We specify fixings and terminations with the exposure of the site in mind, and pay particular attention to verge and drip detailing on exposed elevations.