How to Make a Good Caulk Joint

Good Caulk Joint vs. Bad Caulk Joint

Caulk joints often fail because most joints are packed full of caulk and call it done. That will inevitably lead to failure.

For a caulk joint to perform as intended, it needs an hour glass shape so that it can stretch. To ensure that, you need to use a foam backer rod. The foam compresses which allows it to stay in place and helps ensure the caulk maintains the right shape.

 As the two adjacent objects shift apart or laterally, the caulk is able to stretch without breaking the bond. A big glob of caulk doesn't stretch, it will separate from one of the adjacent objects.

Next time you're caulking a joint, spend a few extra dollars and get backer rod.