Closed Cell Backer Rod

Closed Cell Backer Rod is a round, closed-cell polyethylene foam material with a smooth, skin-like texture. It is compatible with butyl, polysulfide, acrylic, polyurethane, silicone, and most cold sealants. It helps prevent mortar from clogging expansion joints and is the preferred material for brick and block expansion joint fillers.  Backer rods help create optimal joint conditions for cold-applied sealants. Whether you’re sealing concrete, wood, glass, or metal, backer rods act as a bond breaker, control joint depth, and reduce sealant use—saving time and material costs.

Available in spools of:

1/2" x 2500'

5/8" x 1550'

3/4"x 1100'

7/8" x 850'

1" x 600'

1 1/4" x 400'