Address: 6553 W 400 North, Greenfield, IN 46140
Email: jason.koch@nmwinc.com

BACKER ROD

Standard Backer Rod

Standard Backer Rod

Standard backer rod is an ideal non-absorbent compressible material inserted into a joint to control sealant depth. It creates a backstop to allow for proper sealant tooling. Backer rod is commonly used in glazing operations, window and door applications, expansion joints, curtain wall joints, partitions, log constructions, pavement joints and repair, and precast units and copings among many other job applications.


Standard backer rod is an extruded round, closed-cell, low-density polyethylene foam material with skin-like outer texture. It is highly flexible and compressible for easy installation; however, it is important to make sure that one does not puncture, stretch, or overly compress backer rod.


Technical Data Sheet

Soft Backer Rod

Soft Backer Rod

Soft backer rod is a soft, gray, pliable non-gassing backup material inserted into an expansion or contraction joint to:


  • Control sealant depth.
  • Create a backstop to allow for proper sealant tooling.
  • Ensure sealant adhesion to joint surfaces only.
  • Yield a proper bond break between backup material and sealant.

Soft backer rod is particularly well suited for specialty applications where standard backer rods are not appropriate. Soft backer rod is ideal in irregular joint applications where self-leveling, flowable sealants are employed. Soft backer rod is also recommended for use with sealants where bubbling concerns are critical. It is compatible with all know cold-applied sealants including butyl, polysulfide, acrylic, polyurethane, and silicone.


Soft backer rod may be used in place of most standard backer rod applications or as a temporary joint seal.


Technical Data Sheet

Open Cell Backer Rod

Open Cell Backer Rod

Open-cell backer rod is an ideal non-gassing backup material, which is inserted into construction and pavement joints to:


  • Control sealant depth.
  • Create a backstop to allow for proper sealant tooling and configuration.
  • Allow for proper sealant airing and yield a proper bond breaker.


Open-cell backer rod is ideal for non-uniform joint sizes and is commonly used in expansion and contraction joints, window glazing, curtain wall construction partitions, precast assemblies and copings, parking decks, bridge construction, and more. 

Open-cell backer rod, an inert material, is compatible physically and chemically with virtually all known hot-pour and cold-applied sealants including silicone and asphalt.


Technical Data Sheet

Hot Backer Rod

Hot Backer Rod

Hot backer rod is an ideal, non-absorbent, compressible backup material inserted into a joint to control sealant depth and create a backstop to:


  • Allow for proper sealant tooling.
  • Allow for proper sealant wetting of the joint surfaces.
  • Yield proper bond breaker between the backup material and sealant.


Hot backer rod is a backstop material for most hot-pour sealants used to fill contraction and expansion joints of concrete highways, runways, driveways, and parking lots. It is compatible with most rubber-asphalt and coal tar-rubber polymer thermoplastic compounds.