How do you use a foam backer rod?
Similarly one may ask, is backer rod necessary?
If bubbling concerns are critical, then the backer rod is necessary for your project. These innovative, foam rods are commonly used in expansion and contraction joints, as well as window and door joint installation and maintenance.
Also question is, is foam backer rod waterproof?
The rods were designed specifically as filler for joints as well as fissures found between materials before the caulking or chinking material is applied to finish the filling process. The gap is then ensured that it is airtight and waterproof due to the filling added in between.
Push the backer rod down into the joint with your hand. The depth of the joint should be a minimum of 1/4 inch and a maximum of 1/2 inch below the concrete pads. This means the backer rod should be this far below the concrete pad surface.