Reasons to Choose Liquid WRBs for Commercial Projects

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A liquid-applied Weather-Resistant Barrier (WRB) is a type of building envelope material used to protect a structure from the elements, such as rain and moisture. It serves as a barrier that prevents water infiltration while allowing moisture vapor to escape from within the building, helping to maintain a comfortable and energy-efficient indoor environment. Here’s how a liquid-applied WRB works:

1. Application Process: A liquid-applied WRB is typically a fluid product that can be sprayed, rolled, or brushed onto the surface of a building’s substrate, which can be materials like wood, concrete, or sheathing panels.

The application process creates a seamless and continuous layer of protection without the joints and seams often associated with traditional WRB materials like house wraps or building paper.

Products Such as:

  • Prosoco R Guard
    • FastFlash
    • Cat 5
    • Spray Wrap MVP
  • Tremco ExoAir
    • ExoAir 220
    • ExoAir 230
    • Securock ExoAir 430 – Sheathing Panel with WRB integrated
  • DensDefy – System to Use with DensGlass Sheathing
    • DensDefy Liquid Flashing
    • DensDefy Transition Membrane
    • DensDefy Liquid Barrier

2. Adhesion and Bonding: The liquid-applied WRB adheres tightly to the substrate, creating a strong bond. This adhesion prevents water and air from infiltrating through cracks, gaps, and joints in the building’s envelope, ensuring a continuous protective layer.

Cracks and Joints are typically filled with a fibrous paste/caulk prior to application of the main WRB. This allows for some construction tolerances, and helps fix some quality issues.

3. Water Resistance: The primary function of a WRB is to resist the penetration of water from rain and other external sources. The liquid-applied WRB forms a barrier that repels water, preventing it from entering the building’s structure. This is crucial for preventing water damage, mold growth, and structural deterioration.

4. Vapor Permeability: While the liquid-applied WRB prevents water from entering the building, it also allows moisture vapor to escape from within. This is important because buildings naturally generate moisture from activities like cooking, showering, and breathing. If this moisture is trapped within the building envelope, it can lead to mold growth and other indoor air quality issues. The vapor permeability of the WRB allows moisture to diffuse out, promoting a healthier indoor environment.

There are options that are Vapor Impermeable, but these should only be used in hot, dry climates.

5. Flexibility and Sealing: Liquid-applied WRBs often have some level of flexibility and elasticity, which allows them to accommodate building movement without cracking or tearing. This is particularly important in areas prone to seismic activity or temperature fluctuations. The flexibility also aids in sealing around penetrations, such as windows, doors, and utility openings, ensuring a tight seal against water and air infiltration.

Liquid-Applied WRBs are especially effective when used with continuous exterior insulation. Monarch Metal provides a number of these systems, including our Thermally Isolated Wall Brackets. These reduce the number of wall penetrations substantially over typical z shaped furring or hat channels. This is a major advantage to liquid-applied products, as these are more flexible, and rated for fastener penetrations.

6. Durability: A well-applied liquid-applied WRB can provide long-lasting protection against the elements. It’s designed to withstand exposure to UV rays, temperature variations, and other environmental stresses, maintaining its integrity over time.

Overall, a liquid-applied WRB provides an effective solution for protecting buildings from water intrusion while allowing moisture vapor to escape. Its seamless and continuous nature, along with its flexibility and durability, make it a popular choice for modern construction projects.

A key to success with any WRB is using a compatible system of products. These products include the sheathing itself, as well as any penetration flashing products. The products listed above are compatible with OSB, Plywood, and Fiberglass Faced Gypsum sheathing.