Quick question about repairing an expansion joint in concrete
JC72| Posted inGeneral Questionson
The joint is about 3ft x ~1.5 inches and the gasket put in place by the builder is long gone. I plan to install a new gasket and top off with the appropriate caulk/sealant.
Since the gap has been neglected I anticipate having add fill with some sort of material.
Q: What material should it be? Sand or soil? I have an opened bag of potting soil that I could tamp down in order to raise the gasket to the correct height. I’m thinking maybe a half inch of fill.
Thoughts?
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Replies
John,
You can use a foam backer rod. This material is usually available at one of the big box stores or online.
You also want to look for a high-quality polyurethane caulk designed to adhere to concrete.
@Steve. That's what I was planning, but I was thinking in case the gap is deeper than the foam backer rod or does it matter that there's a little air space between the bottom of the backer rod and the soil underneath?
John,
Sand would be ideal, but soil would work. If you don't know where you can get a handful of sand, home centers sometimes sell small bags of sand as "sandbox sand."