Trapped moisture is the number one cause of exterior wall damage and can lead to serious structural issues. Proper moisture management, in which the wall cavity stays drier for longer, can prevent system failures and associated callbacks and repair costs. Building on conversations with contractors about their needs in tackling these challenges, we devoted five years to developing HydroGap SA, the first and only self-adhered weather-resistive barrier (WRB) that incorporates a true drainage space.

The 1-mm spacers of the original HydroGap WRB create pathways for moisture to escape, helping to keep walls dry and reduce the risk of moisture damage that can lead to mold and rot. HydroGap SA combines this key feature with a self-adhered component to further reduce the amount of air passing through the membrane.

HydroGap SA’s 100% continuous acrylic adhesive provides sealing around fasteners to help maintain the integrity of the air barrier and is one of the few breathable, fully adhered acrylic adhesives, with a perm rating of 12. While other self-adhered housewraps on the market use a butyl-based adhesive, the acrylic technology provides greater UV resistance and longevity from higher temperatures.

HydroGap SA Samples


Along with the adhesive, we added a mesh-like material that increases the flashing’s tear resistance by 20%, ensuring flexibility and stretch when you’re applying tension to it. A reinforcement scrim helps hold the housewrap tight as you put it on the wall to avoid wrinkles, and because it is a pressure-sensitive adhesive, it can be adjusted or repositioned before it’s rolled.

As you’re installing it, you have peace of mind knowing that any fasteners you’re putting through the cladding are now sealed, and the product’s full contact with sheathing eliminates the potential for blow-off. Additionally, the flashing won’t move due to a house’s positive or negative pressure, which diminishes the worry for ballooning. HydroGap SA makes it easy to maintain mechanical overlaps, allowing the housewrap to overlap the top of the window nailing fin rather than relying on the seam tape alone.

HydroGap SA’s vapor permeance rating of 12 makes it a good choice for mixed-season climates, and it can be installed in temperatures as low as 25 degrees F. Regions with wind-driven rain would benefit greatly from having a drainable and self-adhered product.

BuildBetter with HydroGap SA.


  • Width – 4.75 ft (1.45m)
  • Length per Roll – 80 ft (24.38m)
  • Max. UV Exposure – 120 days
  • Composition – Polypropylene Tri-Laminate
  • Vapor Permeability – 12 Perms
  • Adhesion – Continuous Acrylic
  • Warranty – 15 years (product) or 20 years (system)

HydroGap SA will be coming to market in February 2021. Do you have questions about the upcoming launch? Contact us today!