Backer Rod Foam Material for Expansion Joint

BACKER ROD SUPPORT MATERIAL BETWEEN COPING AND DECK
Often called backer rod, this foam material helps support the deck-o-seal material is stuffed into a deep joint and serves as a level supporting grade so that the Deck-O-Seal can be poured evenly.  Sold per Foot. 

The purpose of the Backer Rod material is to create a shelf inside the joint between the back of the coping stones and the concrete decking.  This shelf provides uniform support for the application of the self-leveling, Expansion Joint Filler, such as Deck-O-Seal.  

By using Backer Rod, you are decreasing the amount of Expansion Joint fill materials and thus lowering your costs.