How to Choose the Right Liquid Waterproofing Membrane

Building structures are exposed to water all the time, which makes proper waterproofing an absolute necessity. Whether you’re stopping rain seeping in through the roof of your house or keeping the water in a swimming pool, choosing the most suitable membrane for the job will save you time and money in the long run.

Let’s explore the range of liquid waterproofing membranes on the market and how to ensure your building is properly protected from the elements.

Types of Liquid Waterproofing Membranes

Liquid waterproofing membranes are typically made from a combination of resins, polymers, and other additives. They can be applied using a range of methods including spraying, rolling, or brushing, and each type offers different coverage, composition and performance qualities.

Common types include:

• Polyurethane Membranes: This type offers exceptional flexibility and high durability thanks to the seamless, strong barrier it creates against water. It’s important to note that they often require highly skilled application to ensure effective protection.
• Acrylic Membranes: Acrylic membranes are easy to apply and work well in areas exposed to UV rays, making them a popular choice for roofs, terraces, and balconies. Before choosing, be aware that they might need more frequent maintenance than other types.
• Cementitious Membranes: Commonly used for swimming pools and water tanks. However, it’s not the best choice for spaces that experience a lot of movement unless the joints are detailed.
• Bituminous Membranes: Areas with no UV rays. A cost effective solutions for retaining walls.

Key Factors to Consider

There are some key considerations to take into account when choosing the most suitable type of liquid waterproofing membrane.

Think about how important ease of installation is for your project. More complex installation requires an expert, which can cost time and money, or if you attempt it yourself, there’s more room for error—rework is expensive, so getting it right the first time is essential for keeping the project on track.

Take time to understand any site-specific environmental concerns. Areas likely to experience heavy rainfall, high UV exposure or other extreme weather will require different properties from waterproofing membranes.

What to Look for in Your Liquid Waterproofing Membrane

Surface Compatibility

A critical factor to consider is the type of substrate or underlying layer you’ll be applying the membrane to. Different substrates—such as concrete, wood, metal, or existing waterproofing layers—can affect the performance and adhesion of your membrane.

Polyurethane’s flexibility makes it ideal for concrete, wood or metal substrates as it can cope with any expansion or contraction of the underlying layer.

Acrylic membranes also work well with a concrete substrate thanks to the ease of application and UV resistance qualities.

Bituminous membranes create a durable waterproof seal, making them compatible with metal substrates and masonry surfaces.

It’s also essential to ensure the surface is prepared properly before application, which can include cleaning, smoothing, and priming.

Application Methods

Different membranes also require varied application methods.

Polyurethane membranes:

• Generally applied in two layers using a brush or roller but here are versions that can achieve the required thickness in 1 coat.
• The first layer should be applied a few hours after priming
• The second layer follows 8–24 hours later

Acrylic membranes:

• Applied using a trowel, brush, or roller
• Smooth and even coating is required for effectiveness

Bituminous membranes:

• Applied using brush or roller.
• Generally applied in 2 layers.

It’s important to cover all holes and let each coat dry completely before adding more layers or topcoats. Make sure to do this within the recommended curing time for the best results.

Durability and Longevity

The durability and lifespan of a liquid waterproofing membrane should also influence your choice. Polyurethane typically lasts the longest, with acrylic membranes needing more frequent replacement.

The key to getting the most out of any membrane is proper installation and regular maintenance.

Manufacturer Reputation and Reviews

Always consider the reputation of the brand you’re buying from or the contractor you’re working with. Read customer reviews and establish details around warranty and customer support.

A trusted supplier will be there for you throughout the entire journey, from helping you choose the right product to supporting you after installation. They should be happy to answer your questions and provide advice when you need it.

Compliance with Building Codes

As with most building projects, your membrane choice must be compliant with local building regulations and standards. Consider the necessary certifications, and that it must pass inspection and approval.

Speak to a trusted supplier, like the team here at Illawarra Industrial Supplies, for compliance advice for your specific project.

Maintenance and Repair Options

Even the most durable waterproofing membranes may need maintenance or repairs over time. Regular inspections allow damage, cracks or wear to be spotted early so that appropriate action can be taken.

Acrylic membranes tend to be the easiest to repair, making them a solid choice for DIY projects. On the other hand, polyurethane membranes should last longer without needing fixes, but once they do, professional help is required to ensure the job is done correctly.

Find the Right Liquid Waterproofing Membrane for Your Project Today

Illawarra Industrial Supplies is here for all your liquid waterproofing membrane needs and concerns. We’re here to help you with material selection, application methods, and tips on working within your building’s specific environment or temperature conditions.

Choosing us as your waterproofing expert means you can rely on professional and quality support for every stage of your project. Contact the team today by filling out the form on our website or calling (02) 4271 3888.