25RALeakBarrier 25RA is a premium-grade, specially formulated SBS self-adhered flashing membrane designed to provide superior moisture protection in critical areas of construction. Engineered with a focus on durability and ease of installation, this self-adhered flashing is an essential component for ensuring the integrity of the building envelope. LeakBarrier 25RA is designed for use on vertical walls and other non-roofing applications.


LeakBarrier 25RA is a versatile flashing option that offers a moisture barrier around many design details, including window and door openings, inside and outside corners of sheathing, electrical and plumbing penetrations, wall-to-wall tie-ins, deck-to-side wall transitions, behind stone and masonry walls, sheathing panel seams, foundation sill plates, behind stucco finishes, and many other non-roofing applications.

Features and Benefits

  • Durable Defense: The 25 mil thickness offers exceptional tear and puncture resistance and is self-sealing, ensuring long-lasting protection against the elements.
  • Self-Adhering: The adhesive backing simplifies installation, eliminating the need for additional adhesives or fasteners.
  • Watertight Seal: Provides a secure and waterproof barrier around joints, seams, and penetrations, preventing water infiltration.
  • Versatile Application: Ideal for windows, doors, sidewall transitions, roof to wall transitions and other vulnerable areas.
  • Time and Cost Savings: Easy installation reduces labor time and associated costs.
  • Testing: AAMA 711 compliant
  • UV Exposure:  90 Days gives extended exposure when you need more time.
  • Economics: Cost-effective barrier against bulk water and moisture vapor

Performance and Installation

  • Performance: LeakBarrier 25RA should be applied within the temperature range of 40 °F (4.4 °C) to 120 °F (48.9 °C) for best adhesion. Prompt coverage is advised to limit exposure to under 90 days, and it’s essential to inspect the product for any damage that might affect its capabilities. It is critically important to note that LeakBarrier 25RA is strictly incompatible with EPDM or plasticized PVC membranes, and should not be used in conjunction with these materials under any circumstances. Always verify compatibility with manufacturers. Avoid fastening the product when applied horizontally or on slopes less than 60°. The compatibility of sealants may vary; therefore, it is crucial to use only sealants that are compatible with asphalt-based products to prevent damage to the adhesive side of LeakBarrier 25RA. Adherence to the recommended sealant application guidelines is necessary for ensuring the product’s effectiveness.
  • Installation: Ensure surfaces are dry, clean, and smooth before installing LeakBarrier 25RA, removing any dirt, debris, or sharp edges. All surfaces must be even, without any voids or damage. Repair any imperfections before applying the membrane. A primer is necessary on certain surfaces like gypsum board (including Dens-Glass Gold), concrete, and masonry. Always conduct a field test on a small area with LeakBarrier 25RA for all substrates to check adhesion. If adhesion is not satisfactory, use a compatible primer as per manufacturer’s instructions. If primer is used, surfaces not covered by the membrane on the same day need to be primed again. Always use a j-roller to apply consistent pressure across the flashing membrane, ensuring a strong and dependable bond is formed.

Product Characteristics

  • Thickness: 25 mil
  • Roll Widths and Lengths: Available in 4", 6", 9", 12”, 18", 24" and 36" widths by 75' lengths to accommodate different application needs
  • Backing: Self-adhesive specially formulated SBS compound for enhanced waterproofing
  • Surface Film: Enhanced polypropylene, which is thermally stable over a wide temperature range; prevents edge lifting and tunneling
  • Release Liner: Removable silicon treated release liner on bottom adhesive side
  • Service Temperature: Withstands temperature of up to 220°F
  • Application Temperature: Best when used between 40°F to 120°F

Properties and Attributes

Property Result Minimum Requirement
Tensile strength 368 psi 143 psi – PASS
Water Penetration Resistance around Nails Prior to Thermal Cycling PASS No water in bottom can, on nail shanks or on the underside of the sheathing - PASS
Water Penetration Resistance around Nails After Thermal Cycling PASS No water in bottom can, on nail shanks or on the underside of the sheathing - PASS
90° Peel Adhesion on OSB 2.7 lb/in 1.5 lb/in - PASS
Cold Temperature Pliability PASS No visible signs of cracking - PASS
Self-Resistance to Peeling PASS No visible signs of cracking - PASS
Water Vapor Transmission ASTM E 96 Permeance (US Perms) <0.02 NA
Peel Adhesion ASTM D 1000
(To Primed Steel)
> 15 lb/in width NA
Elongation – Ultimate Failure or Rubberized Asphalt ASTM D412 (Modified Die C) > 500% NA
Softening Point ASTM D 36 200°F – 230°F NA
Low Temperature Pliability ASTM D 146 (Modified) No cracking at -25°F NA

Limitations and Precautions

LeakBarrier 25RA is pressure sensitive, make sure to properly roll flashing with a j-roller to ensure proper adhesion. To achieve the best adhesion performance, it is essential to apply LeakBarrier 25RA within a temperature range of 40°F (4.4°C) to 120°F (48.9°C). Exercise caution when considering the use of LeakBarrier 25RA in environments where it might be exposed to temperatures exceeding its recommended service range, particularly in hot climates or when installed behind fiber cement and metal sidings that absorb significant heat. It’s important to note that LeakBarrier 25RA is suitable for vertical or sloped wall installation. In cases of sloped installations, avoid using fasteners. Promptly cover the product after installation. Before and after installation, thoroughly inspect the product to ensure it is free from any protrusions or damage that could compromise its moisture-resisting properties. Please be aware that LeakBarrier 25RA is not compatible with EPDM or flexible (plasticized) Polyvinyl Chloride (PVC) based products. Additionally, some sealants may not be compatible with LeakBarrier 25RA. For information regarding sealant compatibility, consult the sealant manufacturer. It is crucial to avoid direct exposure of sealant to the adhesive side of LeakBarrier 25RA and ensure that the amount of sealant used adheres to the specified guidelines. We strongly discourage the practice of excessive sealant use, as it is unnecessary and can be detrimental to the performance of the product.


LeakBarrier 25RA is warranted to be free from manufacturer’s defects.

Note: All statements information and data given herein are believed to be accurate and reliable, but are presented without guaranty, warranty, or responsibility of any kind, expressed or implied, except as may be indicated otherwise in this literature.

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