which waterproofing is best for a terrace

Terraces are often one of the happiest places for any homeowner. They are cherished spots for morning coffees, evening relaxation, or hosting lively gatherings. Without proper maintenance, these outdoor spaces can face significant issues. Homeowners often forget that the terrace is one part of the house that is exposed to the varied environmental conditions and that it needs protection too! Waterproofing is crucial in protecting a terrace from the elements, ensuring it remains strong. It is an essential measure to combat issues like roof leakage, ceiling damage, and unsightly stains. In this article, we will talk about why waterproofing your terrace is important, and explore the most effective solutions (which waterproofing is best for a terrace) to ensure your outdoor space remains both functional and aesthetically pleasing.

What Are the Common Threats to Your Terrace?

Rain and Snowmelt

These are the most common threats as they directly expose your terrace to water. Heavy rainfall or snowmelt can saturate the surface, seep through cracks, and lead to leaks in the underlying structure.

Standing Water

If water puddles or pools on your terrace after rain or snowmelt, it indicates improper drainage. Standing water can put stress on the surface of the terrace and eventually lead to leaks.

Ultraviolet (UV) Rays

While sunshine might seem harmless, prolonged exposure to UV rays can degrade waterproofing membranes over time. This can make them brittle, less flexible, and more prone to cracking, reducing their effectiveness.


Extreme heat can cause the terrace surface to expand and contract. This repeated movement can put stress on the terrace and lead to cracks or separations at the seams.

Signs That You Need to Consider Terrace Waterproofing

Water Leaks

The most obvious sign is water leaking into your home from the terrace. This can manifest as damp patches on ceilings or walls below the terrace, especially after heavy rain or periods of snowmelt.

Cracks and Gaps

Cracks in the terrace surface, particularly along the edges or around penetrations like drains, can allow water to seep through. Over time, these cracks can widen and worsen the leaks.

Pooling Water

If water puddles or forms stagnant pools on your terrace after rain, it’s a sign that the drainage system is clogged or the surface isn’t sloped properly to direct water away from the building. This can lead to water seeping into cracks and damaging the underlying structure.

Peeling Paint or Plaster

Moisture seeping through the terrace can cause the paint or plaster on the ceiling or walls below to peel, crack, and flake. This is not only aesthetically unpleasing but also indicates potential water damage beneath the surface.


A white, powdery substance appearing on the terrace surface or walls underneath could be efflorescence. This is caused by water carrying dissolved salts to the surface, which crystallize and leave a white deposit as the water evaporates. It’s a sign of moisture issues within the structure.

Musty Odors

A persistent musty odor in your home, particularly near the terrace, can indicate mold or mildew growth. Mold thrives in damp environments, and a leaky terrace can create the perfect breeding ground

Which Waterproofing is Best for Terrace?

Choosing the right waterproofing system for your terrace depends on several factors like slope, surface condition, budget, and complexity of the shape. Here’s an overview of common options:

1. Liquid-applied Waterproofing Membranes

This popular choice offers ease of application and good versatility. It consists of a liquid coating, typically made from:

  • Polyurethane (PU): Known for its flexibility and good adhesion, PU is a common resin used in these membranes.
  • Acrylic: Similar to PU, acrylic resins offer good waterproofing properties but might be slightly less flexible.


Pros of Liquid-applied Membranes:

  • Easy to apply, even for DIY enthusiasts with proper instructions.
  • Good flexibility to accommodate minor cracks and structural movement.
  • Conforms well to various shapes and details on the terrace.
  • Available in a variety of colors for aesthetics (though waterproofing remains the primary function).

2. Sheet Membranes

This option uses prefabricated sheets of high-density polyethylene (HDPE) or polyvinyl chloride (PVC).

  • The sheets are rolled out on the terrace surface.
  • Seams are overlapped and then heat-welded or glued together to form a watertight seal.


Cons of Sheet Membranes:

  • Joints are vulnerable and tend to open up
  • It is not possible to envelope irregularly shaped terraces with corners and penetrations like drains and these end up being point of failure.
  • Tend to debond from the roof surface

Acrylic Cementitious Waterproofing Coatings

This traditional and budget-friendly method involves applying an acrylic cementitious coating directly to the terrace RCC surface.


  • The cementitious mix typically consists of an acrylic polymer mixed with portland cement,  and waterproofing additives in a strictly recommended ratio.
  • When applied, it forms a hard, yet somewhat flexible, barrier that bonds well with concrete and masonry substrates.


Pros of Cementitious Waterproofing Coatings:

  • Excellent waterproofing at affordable prices and readily available option.
  • Offers good durability and weather resistance.
  • Can be applied directly over existing sound concrete or masonry surfaces.

Seek Professional Help

When it comes to waterproofing, the expertise of a qualified professional for proper assessment and installation is necessary. Sunanda Global is the best waterproofing company to ensure that your terrace remains protected. With its market-driven R&D, Sunanda Global has established itself as a leader in the construction chemicals industry. Along with terrace waterproofing, Sunanda is involved in the kitchen, basement, and bathroom waterproofing, etc. 

The following are some products we use in terrace waterproofing:

Polyalk WP: Acrylic Cementitious Waterproofing Coating

Polyalk WP provides an exceptional waterproofing barrier for terraces, utilizing a polymer-based formula compatible with cement. This waterproofing solution creates a robust, impermeable layer even under moist conditions, making it ideal for regions with heavy rainfall. It enhances concrete durability by preventing carbonation and protects against cracking and peeling with its high flexural strength and adhesion properties. Polyalk WP is particularly effective in shielding terraces from water damage and sulphate attacks, prolonging the structure’s lifespan and maintaining its aesthetic appeal, establishing it as a leading choice for waterproofing needs.

SUNKOTE WP+: UV Resistant, Acrylic Waterproof Coating

Sunkote WP+ is a dependable elastomeric waterproofing coating that’s easy to apply directly to various surfaces using a brush, roller, or spray. This single-component, water-based, fiber-reinforced acrylic formula builds a strong, thick membrane that resists water penetration. It adjusts to thermal changes and can bridge cracks up to 2mm, offering enduring protection. Additionally, Sunkote WP+ is UV resistant and anti-fungal, ensuring it holds up even under severe environmental conditions.

SUNPROOF PU1K: Polyurethane Waterproofing and Sealing Membrane

Sunproof PU1K is a highly flexible and chemically resistant waterproofing solution, ideal for sealing diverse surfaces. This single-component, moisture-cured polyurethane coating dries to form a durable, rubber-like coating that offers seamless waterproof protection. Its ease of use in a single-pack system makes application straightforward, saving both time and labor costs. Sunproof PU1K’s excellent adherence to concrete and flexibility across extreme temperatures guarantee sustained defense against water damage.

Contact Sunanda Global today and secure your home!