Flat Roof Repairs In
North Wales
Found, Fixed, Documented

EPDM fails at details far more often than in the field: corners, upstands, outlets and any point where the membrane was stretched over an awkward shape. Splits and punctures are cleaned, primed and patched with the manufacturer's own components; failed corner details are cut out and remade rather than covered.

The critical rule is compatibility. Bitumen products, solvents and general-purpose sealants attack EPDM. Where a previous repair has used them, the affected area is cut out and replaced back to sound membrane.

Fibreglass cracks where the deck moves, at trim junctions, and where it was laid too thin or cured badly in cold or damp weather. Crazing across a whole surface indicates a cure problem and generally means recoating rather than patching.

Local repairs are ground back to sound laminate, keyed, and rebuilt with matting and resin, then topcoated. Done properly the repair is structurally continuous with the original, which a smear of sealant never is.

Blistering, lifted laps and splits at upstands are the usual felt failures. Blisters are cut, dried, patched and re-welded; laps are re-welded rather than glued. Where felt is generally sound but tired, a liquid overlay across the whole surface can add years at a fraction of replacement cost.

Liquid systems are repaired by cleaning back, priming and recoating with the same product family, and they are also the most practical way to seal complex roofs with lots of penetrations, plant bases and awkward abutments.

A high proportion of flat-roof leaks start with drainage: a blocked outlet, a gutter full of moss, or a rainwater pipe that backs up. Water then sits deeper and longer than the roof was designed for, and finds any weakness. Clearing outlets and keeping the surface free of debris is the cheapest maintenance there is.

Where a roof ponds because the falls are wrong rather than because it is blocked, no repair will make it last. We will tell you that clearly and quote the corrective work: usually tapered insulation or new firrings under a new covering.

Where a felt, asphalt or tired GRP roof is leaking in several places but the deck below is still dry and sound, a liquid-applied overlay is often the sensible answer. The surface is cleaned, dried and primed, then a fibre-reinforced liquid membrane is rolled over the entire roof, taken up every upstand and dressed into outlets, curing to one seamless skin with no laps to fail.

The advantage is that the existing covering stays where it is. There is no strip-out, no skip, no exposed deck and no risk of rain getting into the building mid-job, so the work is quicker, cleaner and considerably cheaper than a full replacement. It is particularly useful on roofs with lots of pipes, vents and plant bases where a sheet system would need dozens of hand-formed details.

An overlay is not a way of hiding a wet deck. We probe the deck first, and where the boards or insulation are saturated we say so and quote the strip and replacement instead: a liquid system over trapped moisture simply seals the rot in.