Backer Rod is an easy to compress rope-like celled foam. It is inserted into a clean joint at the required depth before caulking/sealing. Backer Rod creates an even depth and supports the sealant / caulk allowing it to form the proper shape (about 2x as wide as deep).
AVAILABLE IN 1/4" UP TO 6" DIAMETER
What Size Backer Rod? Select a Backer Rod diameter that is about 30% larger than the nominal width of the joint (but not less than 10% of the largest gap). See table at the bottom of this page.
Click here to download Backer Rod Submittal Form
What Size Backer Rod you you need?
1/8”- 3/16”