Nine Water-Resistive Barriers Worth Knowing: A Comprehensive Guide to WRB Products for Building Envelopes

Water-resistive barriers (WRBs) are a critical component of any well-designed building envelope. Positioned behind the exterior cladding, these materials form the primary line of defense against moisture intrusion into the wall assembly. While the terms “weather-resistive barrier” and “water-resistive barrier” are often used interchangeably, building professionals increasingly prefer the more specific term WRB to emphasize its distinct role within the four control layers of a building assembly: water, air, vapor, and thermal. Understanding the differences between these layers is essential because the water-resistive barrier may terminate at the top of a wall beneath a roof overhang, whereas an air barrier must form a continuous assembly from one plane of the building to the next. This guide examines nine WRB products that range from time-tested standards to innovative newcomers, helping builders and homeowners make informed decisions for their projects.

Traditional WRB Products: Housewraps and Felts

The earliest synthetic WRBs emerged before the International Residential Code (IRC) required them, and several traditional products remain popular due to their proven performance and affordability.

DuPont Tyvek HomeWrap

For many years, the brand name Tyvek was used synonymously with housewrap, and for good reason. Tyvek HomeWrap was the first synthetic WRB to reach the American market, long before building codes mandated such protection. This nonwoven, nonperforated, high-density polyethylene material boasts a perm rating of 56, one of the highest available in the industry. It offers UV resistance for up to 120 days of exterior exposure.

DuPont has since expanded the Tyvek product line to include specialized variants:

• Tyvek DrainWrap — Slightly less permeable with vertical grooves that create a drainage plane behind siding
• Tyvek ThermaWrap — An insulating WRB that combines water resistance with thermal performance
• Tyvek StuccoWrap — Designed specifically for stucco and EIFS systems

A standard 9 ft by 150 ft roll of Tyvek HomeWrap costs approximately $150 at big-box retailers. Fasteners and compatible tape are required for proper installation.

Henry Jumbo Tex

Curiously, the only product the IRC specifically lists as a WRB for walls is type 1, No. 15 asphalt felt, which was originally designed for roofing. Even more surprising is that modern felt is primarily made from asphalt-impregnated recycled paper. For builders who appreciate the qualities of felt but want a product engineered specifically for walls, Henry Jumbo Tex offers a compelling alternative.

Made from virgin organic material, Jumbo Tex is asphalt-saturated kraft paper that meets IRC criteria for WRB applications. It works behind any type of siding and offers a higher perm rating than traditional roofing felt. Available options include 20-minute and 60-minute water-resistive grades, as well as two-ply products for enhanced durability. Like other felt and paper products, Jumbo Tex must be covered quickly since it has no UV stability. A 40-inch roll covering 324 sq ft typically costs under $20, making it one of the most economical WRB choices.

Integrated Sheathing Systems: Combining Structure and WRB

A growing trend in residential construction is the integration of WRB functionality directly into structural sheathing panels. These systems reduce labor by combining two steps into one and often improve overall performance through factory-applied coatings and engineered tape systems.

Huber ZIP System Sheathing

Huber Engineered Woods introduced ZIP System sheathing alongside the launch of the first iPhone, and both were revolutionary in their respective fields. ZIP panels consist of OSB with a phenolic resin-impregnated covering that serves as both structural sheathing and a code-approved WRB. The system uses specifically designed seam-sealing and flashing tapes along with fluid-flashing products to create an airtight, water-resistant envelope. The panel coating has a perm rating between 12 and 16 and can be exposed for up to 180 days before siding installation.

Huber has since expanded the line with ZIP System R-sheathing, which adds a foam insulation layer to provide thermal control as well. Pricing varies significantly by region, with a 4 ft by 8 ft sheet of 7/16-inch ZIP System sheathing ranging from approximately $16 in Texas to $30 in Connecticut. A roll of seam tape sufficient for eight sheets costs between $27 and $33 depending on location.

LP WeatherLogic

LP Building Solutions applied their SmartSide technology to OSB panels to create LP WeatherLogic, a structural sheathing with a water-resistive paper overlay. When properly taped and flashed, the panel provides a code-approved WRB integrated directly into the sheathing. LP offers acrylic tape in 3-3/4-inch and 6-inch widths for seam sealing and window, door, and penetration flashing, with each roll including a squeegee for proper bonding.

Currently available only in 7/16-inch panels approved for walls, LP plans to release roof sheathing, additional panel sizes, and more accessories. The product is rated at just over 5 perms and can be exposed for up to six months. Pricing remains competitive, with a builder in Alabama reporting 4 ft by 8 ft sheets at $15 and seam tape at $27 per roll.

Advanced Drainable and Peel-and-Stick WRBs

Modern building science has driven the development of WRBs that address specific performance challenges, such as providing drainage behind cladding or offering self-adhered application for maximum continuity.

Benjamin Obdyke HydroGap

Benjamin Obdyke developed their first drainable housewrap by consulting research from Building Science Corporation to determine the optimal gap geometry. Launched in 2011, HydroGap Drainable Housewrap is a laminated product featuring a waterproof film sandwiched between nonwoven polypropylene layers that provide strength and UV resistance. The outer surface incorporates rigid 1 mm spacers that create a defined drainage plane behind the siding, ensuring that any moisture that penetrates the cladding can drain freely.

HydroGap is rated at 16 perms and can be exposed for 120 days. A 5 ft by 100 ft roll sells directly from Benjamin Obdyke for approximately $140.

Henry Blueskin VP100

Henry has long been a leader in sealants, tapes, and adhesives, but most of these products are not breathable. Blueskin VP100 changed that with a peel-and-stick WRB that achieves a perm rating of 33 while maintaining self-adhered convenience. The product features an engineered film with a patented permeable adhesive, making it one of the few vapor-permeable peel-and-stick membranes on the market.

Certain substrates and cold-temperature applications may require a primer, and compatible Henry flashing products are necessary to maintain the warranty. A 4 ft by 100 ft roll costs approximately $250, though pricing varies regionally.

Dorken Delta-Vent SA

European manufacturers have often led the way in innovative building envelope products, and Dorken is a prime example. The company began making finishes in 1892, released their first synthetic roofing underlayment in the 1960s, and had a UV-resistant WRB for open-joint siding by 1999. Their current premium product, Delta-Vent SA, features protective spun-bonded polypropylene outer layers protecting a polymeric water-resistive membrane. It achieves a high 50 perm rating and includes a one-of-a-kind lap-sealing system.

The suggested retail price for a 4 ft 11 in by 115 ft roll is approximately $565, with special project pricing available through regional sales representatives.

Pro Clima Solitex Mento

Pro Clima, a German company distributed by 475 High Performance Building Supply, offers a main line of WRBs suitable for both walls and roofs. The Solitex Mento series includes three variants: the 1000, 3000 Connect, and 5000 Connect. All are layered products with a polymer blend sandwiched between protective layers, all rated at 38 perms. The product numbers correspond to increasing thickness and durability, with exposure limits of three, four, and six months respectively. When installing a rainscreen assembly over these products, builders can use Tescon Naideck batten tape behind furring strips to create a WRB with no vulnerable fastener penetrations. Pricing ranges from $220 for Mento 1000 to $350 for Mento 5000 Connect for a 59-inch by 164-foot roll.

Fluid-Applied WRBs and Product Comparison

Prosoco CAT 5

Prosoco tests their fluid-applied water and air barriers to failure in high-rise commercial construction, giving them confidence in the durability of their entire product line. Their most durable offering, CAT 5, is a silyl-terminated polyether that is rolled onto the substrate. Because it is moisture-activated and rated at 18 perms, CAT 5 can be applied to surfaces that are damp from weather or other conditions. It can be exposed for up to a full year before the final cladding is installed.

CAT 5 works in tandem with Prosoco’s fiber-reinforced Joint and Seam filler and FastFlash fluid-applied flashing. While many jobs require only one coat, two coats are recommended for OSB sheathing. A 5-gallon bucket costs approximately $560 and covers up to 500 sq ft, depending on substrate absorption.

Key Product Comparison Table

When selecting a WRB, builders must consider the full building envelope design principles for their project. Factors such as climate zone, cladding type, wall assembly design, and budget all influence which product is most appropriate.

In climate zones with high rainfall, a drainable housewrap such as HydroGap or a fluid-applied system like Prosoco CAT 5 may offer superior performance. In hot-humid climates, higher perm ratings are generally preferred to allow wall assemblies to dry to the exterior. For projects where speed and simplicity are priorities, integrated sheathing systems such as ZIP System or LP WeatherLogic eliminate an entire installation step by combining structural sheathing with WRB functionality.

The relationship between WRBs and other control layers deserves careful attention. While some WRBs can serve as air barriers on walls, this is only one dimension of the air-control assembly, which must form a continuous connection from one plane of the building to the next. Similarly, vapor barriers serve a different function from water-resistive barriers, and using the wrong product in the wrong location can trap moisture within wall assemblies rather than protecting them.

Building insulation systems must also be coordinated with WRB selection to ensure that the thermal control layer is properly protected from moisture and that the assembly can dry effectively. A well-designed wall assembly considers all four control layers together, with the WRB positioned appropriately within the system.

Installation quality is critical regardless of which WRB product is selected. Common installation errors that compromise WRB performance include:

1. Inadequate lap joints at horizontal and vertical seams
2. Improper flashing at window and door openings
3. Fastener penetrations that are not sealed
4. Tearing or puncturing the WRB during installation
5. Exceeding the specified UV exposure period before covering with cladding
6. Failing to use manufacturer-compatible tapes and flashings
7. Installing the WRB in temperatures outside the recommended range

Each product category has distinct installation requirements. Housewraps and felts require careful attention to lap sequencing and fastener spacing. Integrated sheathing systems demand meticulous tape application with a squeegee for proper adhesion. Peel-and-stick membranes need clean, primed substrates and careful handling to avoid contamination. Fluid-applied systems require proper surface preparation, consistent coverage rates, and adequate curing time between coats.

The evolution of WRB technology continues to accelerate. Manufacturers are developing products that combine multiple control layers, offer extended UV exposure limits, and simplify installation through integrated accessories. As building codes become more demanding and building science understanding deepens, the range of available WRB options will continue to expand. For builders and designers, staying informed about these developments is essential to constructing durable, high-performance buildings that stand the test of time.