Located between patio slabs at a house in Southern California. Am looking to possibly replace it during the cosmetic repairs planned for the area. Even if I don't replace it, am wondering what this stuff is called and what it's supposed to do.
this post was submitted on 25 May 2026
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What is this thing?
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I'm not sure if that's any sort of specialty material, but around my area in south Mississippi, they tend to just use thin strips of wood. Its there to help accomodate for thermal expansion and contraction between hot and cold seasons and try to reduce stress and cracks in the concrete between slabs.
Plastic, especially non UV resistant plastic, seems like a terrible material for an expansion joint. It also looks very short.