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?