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HomeWhat is PU Coating and How to Use it in Waterproofing?
Nov 16, 2025
Water seepage can silently damage homes, offices and commercial buildings across India. With shifting weather, heavy rains and fluctuating temperatures making surfaces more vulnerable than ever, many people seek waterproofing solutions to keep their properties dry and protected.
Among new options available, PU coating is gaining attention for waterproofing roofs, terraces and bathrooms. But what exactly is a PU coating and how does it work against leaks, cracks and moisture?
What is PU Coating?
PU coating, short for polyurethane coating, is a synthetic liquid membrane applied as a protective film on different surfaces. Once cured, PU forms a seamless, elastic and weather-resistant barrier that keeps water from entering the material underneath. The technology first gained prominence in textiles and industrial paints and is now widely used in the construction sector as a smart solution to water-related issues.
Key Features of PU Coating
- Flexible: Moves with minor cracks or shifts in surfaces
- Durable: Resists wear, UV rays, chemicals and abrasions
- Versatile: Suitable for concrete, metal, wood and many common materials
- Easy Application: Can be applied by brush, roller or spray
PU coating for waterproofing is increasingly used in Indian homes because it adapts well to changing temperatures and high rainfall, common in many regions across the country.
Why Choose PU Coating for Waterproofing?
Indian buildings often face water damage due to the monsoon, poor drainage and flaws in traditional waterproofing methods. PU coating brings several advantages over older treatments.
Benefits of PU Coating in the Indian Market
- Seamless waterproof barrier that stops water ingress
- Absorbs structural movement without cracking
- UV resistance, retaining colour and strength in sunlight
- Withstands temperature changes in the Indian climate
- Sticks well to various surfaces used locally
- Minimises maintenance and reapplication over time
- Effective for rooftops, terraces, water tanks, bathrooms and basements
Applications in Construction
PU coating is suitable for:
- Roofs and terraces
- Bathrooms and toilets
- Water tanks, both potable and non-potable
- Basement walls and floors
- Balconies and podiums
- Industrial settings as protective lining
How to Use PU Coating for Waterproofing?
Step 1: Surface Preparation
- The surface must be dry, clean and free of dust, oil or old paint.
- Cracks and holes should be filled with suitable sealant or mastic.
Step 2: Application
- Use brush, roller or spray depending on the type of PU.
- Apply at least two coats for robust protection, allow the first layer to dry fully before the next.
- Ensure even coverage, especially at joints and weak spots.
- Avoid application during rain or on wet surfaces.
Step 3: Aftercare
- Inspect regularly for wear or damage
- Reapply in case of abrasion or punctures
- Maintain drainage systems to support waterproofing
How PU Coating Compares to Other Waterproofing Options?
- PU coating is more flexible and longer lasting than traditional cementitious or bitumen-based systems.
- Liquid application means there are no joints for water to penetrate, unlike sheet membranes.
- Rapid curing and crack-bridging properties offer added peace of mind in unpredictable weather conditions.
Why Choose Astral Trubuild TRU PU?
Astral Trubuild TRU PU offers robust and versatile protection using its advanced PU-based membrane. It is a single-component liquid making application straightforward, with reliable flexibility across many temperatures. The bitumen-modified formula stands up well to oxidation and prevents brittleness, maintaining effectiveness through changing conditions. Its adhesive qualities let it bond to various surfaces, while the membrane covers cracks up to 2 mm.
TRU PU is suitable for waterproofing terraces, basements, foundations, retaining walls, gardens and roof areas that are shielded from direct sun. For Indian environments, TRU PU is a practical choice for long-lasting moisture defence.
PU coating for waterproofing helps keep Indian buildings safe from leaks. It also cuts maintenance costs, improves longevity and fits a variety of application needs. When chosen and installed as per site requirements, it delivers layers of protection that stand up to local climate. Explore a range of PU waterproofing solutions at Astral Trubuild.
FAQ
What is PU coating?
PU coating is a liquid-applied polyurethane membrane for waterproofing surfaces and protecting them from water damage.
How is PU coating applied for waterproofing?
PU is brushed, rolled or sprayed onto dry, prepared surfaces and forms a seamless water barrier once cured.
Is PU coating effective in India’s climate?
Yes, PU coating handles temperature swings, UV exposure and monsoon rains making it one of the best choices for waterproofing in India.
