CRL Sof® Rod 3/8" x 3600 ft Foam Backer Rod for Sealant

• Controls sealant depth and functions as an effective bond breaker
• Compatible with cold-applied sealants and many hot-pour sealants (observe temperature limits)
• Soft, compressible polyolefin foam for easy installation

CRL Sof® Rod (SKU SR38B) is a dual-celled backer rod designed for durable sealant joints. Combining the benefits of both open- and closed-cell backer rods, this extruded polyolefin foam has a non-absorbent outer skin and a resilient internal structure that minimizes out-gassing and prevents sealant bubbling and failure. Chemically inert and compatible with virtually all known cold-applied sealants, CRL Sof® Rod is suitable for self-leveling and non-sag formulations used in glazing, curtain wall construction, and general joint sealing.

CRL Sof® Rod is available in diameters from 3/8” to 2” (10 to 51 mm).

Temperature Limits:
-45° to 160°F (-43° to 71°C)

Application:
Use as a backer rod for glazing, curtain wall construction, partitions, parking decks, bridge construction, modular home gasketing, and log home chinking. Ideal as a sealant backing for expansion and control joints where a reliable bond breaker is required.

Size Selection:
Select a CRL Sof® Rod approximately 25–50% larger than the joint width to ensure a tight fit and proper control of sealant bead depth. Correct sizing prevents backside adhesion and helps achieve the recommended sealant "hourglass" profile.

Storage:
Store in a well-ventilated area out of direct sunlight. Keep away from heat sources and open flames.

Joint Preparation:

• New Joints: Clean thoroughly to remove form-release agents, curing compounds, or debris. Ensure the joint is clean and dry before applying sealant.
• Repairing Old Joints: Remove all old sealant or filler. Use wire brushing and air blasting for effective cleaning. If using an air