What happens if I cut the backer rod and exposed the damaged cells to the sealant?
Outgassing can occur, depending on the type of backer rod used. Outgassing appears as bubbles in the sealant which may shorten its service life. Contractors get call backs for bubbles in the cured sealant because the closed cell backer rod is ruptured during insertion into the joint reservoir. Usually this condition causes the gas from within the ruptured cells to create bubbles in the soft uncured sealant. To avoid this condition SOF® ROD or Dual Rod® is specified. Unlike closed cell backer rod Dual Rod® and SOF® ROD are non gassing if ruptured by the contractor during placement into the joint opening.
