Used for concrete precast building. Backer rod is inserted between the concrete panels to fill the gap, thus providing a ‘backer’ for the caulking that is applied. When used correctly, caulking within the joint can freely expand and contract as it was intended to do. These backer rods can be used around doors, windows, wall joints, as well as foundations. A backer rod is recommended in numerous construction applications because it:
Saves caulking material by filling in most of the gaps
Provides additional insulation and increase energy efficiency of a house
Blocks drafts, giving additional quality to window installations
