RedGard vs Aqua Defense: The Ultimate Guide to Waterproofing Solutions

When it comes to waterproofing solutions for homes and buildings, two names consistently stand out: RedGard and Aqua Defense. Both are well-known in the construction industry for their reliability and effectiveness in providing protection against water damage. In this comprehensive guide, we’ll dive deep into the world of RedGard and Aqua Defense, exploring their histories, product differences, applications, advantages, limitations, cost comparisons, and how to choose the best solution for your waterproofing needs.

History and background

RedGard, a product by Custom Building Products, was first introduced in the 1990s as a waterproofing solution for residential and commercial applications. It quickly gained popularity due to its ease of use and effectiveness. On the other hand, Aqua Defense, produced by Mapei, has been a staple in the waterproofing industry since the 1980s. Over the years, both companies have continuously refined their products, offering solutions that cater to a wide range of waterproofing needs.


Though both RedGard and Aqua Defense are designed to protect against water damage, there are some key differences between their product lines. RedGard is a liquid-applied, elastomeric membrane that dries to form a flexible, rubber-like barrier.

It is available in two formulations: RedGard Waterproofing and Crack Prevention Membrane and RedGard SpeedCoat Waterproofing Membrane. Aqua Defense, on the other hand, is a roll-on, single-component, liquid waterproofing membrane. It is available in two versions: Aqua Defense and Aqua Defense Express.

How RedGard Works

Red Guard vs Aqua Defense: The Ultimate Guide to Waterproofing Solutions

RedGard works by creating a seamless, waterproof barrier on surfaces. It is applied as a liquid, which penetrates deep into the substrate to fill any gaps, pores, or cracks. Upon drying, RedGard forms a tough, rubber-like membrane that is resistant to water, chemicals, and UV rays. The flexibility of the membrane ensures that it can accommodate slight movements or shifts in the structure without compromising its integrity.

How Aqua Defense Works

Aqua Defense operates on a similar principle as RedGard. It is applied as a liquid, forming a seamless, waterproof barrier upon drying. However, Aqua Defense also incorporates advanced polymer technology, which provides increased flexibility and improved adhesion to a variety of substrates. This technology ensures that Aqua Defense remains effective even in challenging environments or applications.

Application methods

Both of them are easy to apply, and their application methods are quite similar. They can be applied with a brush, roller, or trowel, depending on the specific product and the surface being treated. The key to a successful application lies in proper surface preparation and following the manufacturer’s guidelines regarding the number of coats, drying times, and compatibility with other materials.

Advantages of using RedGard

RedGard offers several advantages as a waterproofing solution:

  • Easy application
  • Versatile and compatible with various substrates
  • Excellent crack-bridging capabilities
  • Long-lasting protection
  • Resistant to chemicals and UV rays

Advantages of using Aqua Defense

Red Guard vs Aqua Defense: The Ultimate Guide to Waterproofing Solutions

Aqua Defense also has numerous advantages:

  • Quick-drying formula
  • Advanced polymer technology for improved flexibility and adhesion
  • Can be applied to damp surfaces
  • Compatible with various substrates
  • Resistant to chemicals, mold, and mildew
  • Long-lasting protection

RedGard Limitations

Despite its many benefits, RedGard also has some limitations:

  • Longer drying time compared to Aqua Defense
  • May not adhere as effectively to damp surfaces
  • Requires multiple coats for optimal performance
  • Some users may find the odor strong during the application

Aqua Defense Limitations

This waterproofing barrier has a few limitations too:

  • Can be more expensive than RedGard
  • May require additional reinforcement in high-stress areas
  • Limited compatibility with some adhesives and coatings

Cost Comparison

In terms of cost, RedGard tends to be more affordable than Aqua Defense. However, the specific cost of each product depends on factors such as the size of the area being treated and the number of coats required. It is essential to consider not only the initial cost but also the long-term value and effectiveness of the product when making a decision.

How to Choose?

When choosing between them, consider the following factors:

  • Budget: If you’re working within a tight budget, RedGard may be a more cost-effective option.
  • Application environment: Aqua Defense can be applied to damp surfaces and dries faster than RedGard, making it a better choice for time-sensitive projects or damp environments.
  • Compatibility: Ensure that the chosen product is compatible with the materials used in your project.
  • Specific needs: Assess your project’s unique requirements, such as crack bridging, chemical resistance, or the need for a quick-drying solution, to determine the most suitable product.


paint over RedGard or Aqua Defense

Can I paint over RedGard or Aqua Defense?

It is not recommended to paint directly over their membranes. If you need to paint a surface, it should be done before applying the waterproofing membrane.

How long do RedGard and Aqua Defense membranes last?

When properly installed and maintained, both of their membranes can provide long-lasting protection against water damage. The actual lifespan of the membrane depends on various factors, such as environmental conditions and exposure to chemicals or abrasion.

Are RedGard and Aqua Defense safe for potable water applications?

Neither of these products is specifically designed for potable water applications. Consult the manufacturer for more information on their suitability in such cases.

Can I use RedGard or Aqua Defense on a roof?

Both products can be used for waterproofing flat roofs or roof decks when installed according to the manufacturer’s guidelines. However, they are not intended for pitched roofs or as a primary roofing material.

How should I store RedGard and Aqua Defense products?

RedGard and Aqua Defense products

Store them in a cool, dry place, away from direct sunlight and freezing temperatures. Keep the containers tightly sealed when not in use to prevent contamination or evaporation of the product.

Can I use RedGard or Aqua Defense in a swimming pool or fountain?

They are not specifically designed for use in swimming pools or fountains. However, they can be used for waterproofing adjacent areas or water features with limited water exposure. For applications involving continuous immersion in water, it is recommended to consult the manufacturer or use a product specifically designed for such purposes.

Can RedGard or Aqua Defense be applied over existing tiles?

It is not recommended to apply both of them directly over the existing tile. The tile should be removed, and the substrate should be cleaned and prepared according to the manufacturer’s guidelines before applying the waterproofing membrane.

Are RedGard and Aqua Defense suitable for use with in-floor heating systems?

Yes, both of them can be used with in-floor heating systems. However, it is essential to follow the manufacturer’s guidelines for compatibility and installation with the specific heating system being used. Proper installation will ensure the effectiveness of the waterproofing membrane and the efficiency of the heating system.


Ultimately, the choice between them depends on your specific waterproofing needs, budget, and project requirements. Both products offer excellent waterproofing solutions, but they differ in terms of application, drying time, and compatibility. By carefully considering your project’s unique circumstances and weighing the advantages and limitations of each product, you can make an informed decision that will provide long-lasting protection against water damage.

So, whether you choose RedGard or Aqua Defense, rest assured that you are investing in a reliable waterproofing solution that will protect your home or building from the damaging effects of water infiltration.