Go to any hardware shop in Sri Lanka and you will see many different waterproofing products on the shelf — tins, powders, liquids, all claiming to "stop leaks 100%". For someone building or renovating a house, this can get confusing fast. So let's break it down simply, the way we explain it to our own customers.

1. Cement-based slurry

This is the most common type, mixed with water and applied like a paste with a brush. It's simple to use and bonds well to concrete, brick and blockwork. It works great for bathrooms, water tanks and areas that will be tiled over. A basic version like Duraseal XP seals the small pores in concrete, while flexible versions like Duraflex Ultra also handle hairline cracking — important since most Sri Lankan buildings develop small cracks over time due to heat movement.

2. Acrylic and polyurethane membranes

These are liquid coatings that dry into a stretchy, rubber-like layer. Because rooftops and open terraces get direct sun and rain, and expand and contract a lot with heat, a stretchy membrane handles this movement far better than a hard cement coating. This is why most roof waterproofing jobs use an acrylic or PU-based system rather than a cement slurry alone.

3. Bonding and admixture products

Some products are not applied as a final coating but mixed into mortar or concrete to improve water resistance and bonding from the inside. These are more of a "behind the scenes" solution used by contractors during construction, rather than something you buy for a quick DIY fix.

So which one should you use?

A simple rule we tell customers:

  • Bathroom floor or wall before tiling → flexible cement-based slurry
  • Rooftop, terrace or exposed slab → acrylic or PU membrane
  • Foundation, retaining wall or water tank → cement-based slurry or crystalline system
  • Big commercial or government project → get a specification from a specialist, don't guess

If your project needs proper site application by trained applicators rather than a DIY job, WaterProofing.lk is Sri Lanka's dedicated waterproofing service specialist, applying certified Supercrete systems with written warranty on everything from homes to hospitals and national infrastructure.

You can browse our full range of waterproofing products, or if you're not sure which one fits your project, just ask us for a free quote — we're happy to guide you.