Willseal Backer Roll | Secondary Pre-Compressed Seal for Vertical Joints
The Willseal Backer Roll is a versatile pre-compressed, self-expanding polyurethane foam seal designed for secondary sealing in vertical construction joints. Built for flexibility and durability, it forms an ideal backing foundation for wet sealant systems, including silicone, polyurethane, polysulfide, and acrylic sealants. Its vapor-permeable, R-value-enhancing structure helps improve energy efficiency and delivers reliable performance in demanding conditions.
Key Benefits of Willseal Backer Roll
- Provides a dependable secondary seal behind wet-applied sealant systems
- Accommodates gaps and seams as small as 1/8 inch for enhanced sealing
- Maintains permanent flexibility, resisting breakdown from rapid joint movement
- Available in rolls and sticks, with optional PSA (pressure-sensitive adhesive) for simplified installation
- No mixing, masking, or priming required, reducing labor time
- Compatible with a variety of Tremco sealants for seamless building envelope integration
- Enhances thermal efficiency by increasing the R-value of joint assemblies
Common Applications
Willseal Backer Roll is designed for secondary expansion and control joints, construction joints behind wet sealants, pre-cast masonry and façade assemblies, EIFS systems, window and flashing installations, and interior environments requiring vapor, dust, acoustical, or air control. Its adaptability makes it a key component for both new builds and retrofit projects.
Packaging and Performance
Available as both pre-cut rolls and sticks, Willseal Backer Roll simplifies field installation with optional PSA backing, ensuring precise, efficient placement. Its vapor-permeable composition ensures long-term compatibility with Tremco’s high-performance sealing solutions.
Product Properties
| Property | Value |
|---|---|
| ASTM C518: Thermal Conductivity | 0.28 to 0.30 Btu-in/hr-ft²-°F |
| ASTM D3574: Ultimate Elongation | 120% ± 20% |
| Foam Color | Black |
| Storage Temperature | 68 °F (20 °C) |
| Temperature Stability | Short term: -40 to 248 °F (-40 to 120 °C) | Long term: -40 to 194 °F (-40 to 90 °C) |
For a breathable, vapor-permeable primary seal, see Willseal 600 Foam. More Tremco joint solutions are available at TremcoSealants.com.
