Most Gulf flat roofs are waterproofed one of two ways: torch-applied APP bituminous membrane, or liquid-applied polyurethane. Membrane is the volume choice — predictable 4 mm thickness, fast coverage on open areas, decades of regional track record. Liquid PU wins where geometry gets complicated: plant platforms, pipe penetrations, upstands, and refurbishment over existing layers.
The honest comparison: membrane is cheaper per square metre on open roof and more forgiving of applicator skill, but every roll edge is a seam, and seams are where leaks start. Liquid systems are seamless and self-flashing around details, but they demand correct substrate moisture, strict coverage rates (typically 1.5 kg/m² in two coats), and weather windows during application.
Ninety percent of the leaks we're called about trace to detailing, not the field membrane: upstands terminated too low (150 mm above finished level is the minimum), missing bond breakers at movement joints, drains not dressed into the outlet, and no protection layer before screed works damage the membrane. Whichever system you choose, spend your supervision hours on the details.
In inverted roof build-ups — standard for accessible roofs here — the membrane sits under XPS insulation and ballast, protected from UV and thermal cycling. That's why pairing membrane choice with the right XPS compressive grade (300 kPa minimum for terraces) matters as much as the membrane itself.
We supply complete systems — membranes, primers, PU liquids, XPS, geotextile and protection boards — with applicator recommendations for every Emirate.
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