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Proven Products & Proven Solutions
Proven Products & Proven Solutions
Closed Cell Backer Rod

Closed Cell Backer Rod

Closed Cell Backer Rod is a round polyethylene foam material that is used to fill log joints, checks and gaps prior to installing chinking and caulk.  Since chinking and caulk do not adhere to it, backer rod serves as a “bond breaker” to allow two-point adhesion of the sealant to the logs on each side of the log joint so that the sealant will expand and contract properly with log movement.

Please Note:  Since Closed Cell Backer Rod requires a larger box than most products with the same weight, it is subject to an oversize shipping charge. We will notify you with the actual shipping cost for your approval prior to shipping.

 

$15.95

Closed Cell Backer Rod is round polyethylene foam that is probably the most popular backer material for filling log joints, checks and gaps prior to installing chinking and caulk.  Since backer rod fills most of the joint or check, you use less chink or caulk, which saves money.  Backer rod also provides firm support for the sealant.  More importantly, since chinking and caulk do not adhere to it, backer rod serves as a “bond breaker”.  Using a bond breaker for backing, the chinking or caulk adheres only to the two sides of the joint (known as “two-point adhesion”).  Two-point adhesion is critical because it allows maximum stretching and compressing of chinking and caulk with natural log movement without cracking or tearing.  

 

The round shape of backer rod also has the advantage of providing a larger adhesion area for the sealant on each side of the joint, increasing the sealants ability to adhere to the wood surfaces.  Closed cell backer rod is available in a wide variety of diameters, making it easy to get the right size for your job.  Backer rod works well for both exterior and interior use.