Flat-roof waterproofing
with liquid rubber — seamless & rain-tight in 6 h

Clean the roof surface with pressure washer or wire brush — fully remove loose bitumen residue, moss, algae and dirt. Pre-fill cracks > 3 mm with bituminous repair compound, mechanically loosen any peeling areas. Substrate must be dust-free and dry for at least 4 h before application.

On heavily weathered bituminous sheets: apply a bitumen primer to stabilise.

Pro tip: Check the roof slope beforehand — if puddles form, we recommend a slope renovation with levelling compound first.

Chimneys, skylights, roof drains and upstands are the weakest points — 80 % of all leaks start here. Embed polyester fleece (60 g/m²) into the wet first coat, roll flush. Minimum 10 cm overlap at wall/upstand edges, cut circular around drains and work U-shaped into the upstand.

At wall connections: pull the fleece at least 15 cm up the wall for a reliable bond.

Pro tip: At chimney connections add a termination bar with sealant — fleece alone isn't enough against thermal movement.

Dilute with 0–5 % water. Apply with brush, lambswool roller or airless sprayer (15–18 MPa, nozzle 0.017–0.023″). Consumption 100–200 g/m². Work evenly in one direction, no gaps or thin spots. On weathered bitumen or porous concrete: deep primer 12 h beforehand recommended.

Particularly careful on fleece-reinforced areas — the coat must fully penetrate the fleece.

Pro tip: With an airless sprayer work against the wind — otherwise half the material lands on the neighbour's wall.

Dust-dry after 2 h, recoatable after 4 h, rain-resistant after 6 h at 23 °C / 50 % RH (manufacturer specification). Wait longer at lower temperatures — applying the second coat too early causes bubbles as residual moisture gets trapped.

Protect the roof from rain and frost during drying — at least 24 h without precipitation required.

Pro tip: Check the weather forecast 48 h ahead — flat-roof coating is not rain-tolerant and needs a stable weather window.

Apply undiluted, cross to the first coat. Consumption again 100–200 g/m². Rain-resistant after 6 h, carefully walkable after 24 h (soft shoes, no point loads), fully load-bearing and cured after 28 days.

On heavily-loaded maintenance paths or frequently walked areas we recommend a third coat for longer service life.

Pro tip: Mark maintenance paths with a contrast-coloured quartz-sand strip — extends service life through targeted wear protection and prevents point loads elsewhere.