Roof Waterproofing With Acrylic Polymer: A Simple Step-by-Step Guide

When it comes to protecting a building from leakage, seepage, and long-term dampness, roof waterproofing plays a critical role. Among the modern solutions available today, acrylic polymer–based waterproofing has become extremely popular for its durability, flexibility, and ease of application. One such high-performance material is Sunkem UPC, an acrylic polymer designed especially for cementitious waterproof coatings.

Below is a clean, step-by-step process to waterproof your roof using Sunkem UPC.

 

1. Introduction: Why Acrylic Polymer Waterproofing?

Acrylic polymer waterproofing systems combine cement with a liquid polymer to create a seamless, flexible coating.
Key benefits include:

  • High UV resistance
  • Strong bonding with concrete
  • Crack-bridging ability
  • Easy brush application
  • Longer service life with a protective screed

This makes it ideal for flat roofs, terraces, balconies, and parapet walls where water exposure is constant.

 

2. Product Selection: Choosing Sunkem UPC

For a reliable waterproofing system, selecting the right product is essential. Sunkem UPC is a premium-grade acrylic polymer specially formulated to mix with cement and create a strong waterproof slurry. It enhances adhesion, increases tensile strength, and improves the overall durability of the coating.

Recommended ratio:
1 part Sunkem UPC : 2 parts fresh cement

 

3. Surface Preparation

A good finish always starts with a clean base. Follow these steps:

  • Clean the roof thoroughly to remove dust, algae, loose mortar, and previous flaky coatings.
  • Check for cracks and fill them with a polymer-modified mortar (using UPC).
  • Ensure drains and slope lines are free to allow proper water flow.

A well-prepared substrate increases the life of the waterproofing system.

 

4. Water Sprinkling on the Roof

Before applying any coating, lightly sprinkle water on the surface to make it SSD (Saturated Surface Dry).
This prevents the cement polymer slurry from drying too quickly and ensures better bonding.

Do not flood the surface—only dampen it.

 

5. Mixing Sunkem UPC With Cement

Prepare a uniform slurry:

  • Take 1 part Sunkem UPC
  • Add 2 parts cement
  • Mix slowly to avoid lumps
  • Maintain a brushable consistency
  • Use the mixture within 30–45 minutes.

 

6. Apply the First Coat

Using a brush:

  • Apply the first coat evenly across the entire roof.
  • Cover corners, joints, and drain areas carefully.
  • Ensure uniform thickness without gaps.

 

7. Apply the Second Coat

Once the first coat is touch-dry:

  • Prepare fresh slurry in the same ratio.
  • Apply the second coat perpendicular to the first coat to avoid pinholes.
  • Allow proper curing for 24 hours.

This dual-coat system forms a seamless protective layer.

 

8. Add a Concrete or Protective Layer

Acrylic polymer coatings must be protected from direct wear and tear. After curing:

  • Lay a 25–40 mm protective screed, or
  • Use tiles/IPS/China Mosaic as per site requirement.

This final layer prevents mechanical damage and enhances the life of the coating.

 

Conclusion

Roof waterproofing doesn’t have to be complicated. With Sunkem UPC acrylic polymer, you get a dependable, flexible, and easy-to-apply system that protects your structure from leaks and seepage for years. By following the simple steps of surface preparation, correct mixing, double coating, and adding a protective layer, you can achieve a durable waterproofing solution for any roof.