Systems
Polyurethane waterproofing in Mauritius: seamless liquid membrane
Cold-applied polyurethane forms a continuous membrane, with no seams or laps, that follows every detail of a roof. It is one of the systems we specify most often in Mauritius on concrete slabs exposed to strong sun and heavy rain.
Why seamless matters
The vast majority of leaks happen at junctions: sheet overlaps, upstands, corners, pipe penetrations, outlets. A liquid membrane cures as a single piece and removes those weak points, including on complex shapes that rolls cannot cover cleanly.
Elasticity and substrate movement
A Mauritian roof expands by day and contracts at night. Polyurethane keeps a high elongation once cured: it moves with the substrate and bridges microcracks instead of tearing, provided reinforcement fabric is embedded at detail points.
UV and heat resistance
An aliphatic polyurethane, or a UV protection topcoat, is essential on an exposed roof. In a light or reflective finish it also lowers the slab's surface temperature and the heat transmitted inside.
- Applicable over concrete, screed, compatible existing membranes
- Trafficable in a reinforced build-up for accessible terraces
- Repairable and re-coatable without full removal
Where it is not the right answer
Polyurethane needs a dry, clean and properly primed substrate. Over a water-saturated slab, untreated permanent ponding or a crumbling surface, another system or preparatory works are required. We say so before the quote, not after.
How we install it
Diagnosis and moisture readings, mechanical preparation, crack repair, substrate-specific primer, fabric-reinforced treatment of every detail point, then cross-applied coats with thickness checks and a photo report.
Frequently asked questions
Is polyurethane waterproofing suitable for the Mauritian climate?
Yes, provided a UV-resistant grade is used and curing times are respected. It is one of the systems best suited to concrete slabs facing the island's heat and rain cycles.
Can it be applied over an existing membrane?
Often yes, if the old membrane is well bonded, compatible and properly prepared. An adhesion test on a trial area settles the question before committing.
How long does a project take?
It depends on the area, substrate condition and weather: polyurethane needs a dry window between coats. The schedule is given with the quote after inspection.
Need a diagnosis on your building?
Free inspection anywhere in Mauritius, written specification and warranted works. Call 606 2500.
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