Where a joint is too shallow for backer rod, such as a lap joint or a joint over a solid backing, polyethylene or PTFE tape is laid at the bottom so sealant adheres only to the side faces. Backer rod serves the same purpose in deeper joints. Bond breaker tape is also used under bridge joints so the center of the sealant band can stretch freely.
No room for rod behind the panel, so lay down bond breaker tape and keep the bead at a quarter inch.
Also heard as
- bond breaker tape
- bond-breaker tape
Related terms
Backer rod
A round foam cord pushed into a joint to set sealant depth and keep the sealant from bonding to the back.
Three-sided adhesion
Sealant bonded to both joint faces and the back of the joint, which locks it in place so it tears when the joint moves.
Bridge joint
A band of sealant laid over the face of a joint, bonding to the surfaces on either side instead of filling the gap.
Band-aid
A bridge joint applied over an existing sealant joint as a repair, without removing the old material.