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Do I need to seal a concrete slab edge to avoid it looking rough?

bigbuster

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Joined
Oct 3, 2025
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18
I built a small, 550 square foot in-law apartment onto my house about three years ago, and I have a question about the foundation.

It's just a slab on top of a footing. I've been looking at the slab edges where the slab meets the footing, and they look pretty rough. It's not smooth at all and it almost looks like there were air pockets in the concrete when it was poured. Since I do not know much about concrete, I was wondering if this is a problem I need to worry about. Does that rough edge need to be sealed, caulked, or filled with something to protect the foundation or is this normal concrete work and not a reason for any concern?
 
That's generally considered a cosmetic issue and a sign of minor subpar workmanship, but for a non-structural area like the edge of a three-year-old slab foundation, it is very unlikely to be a structural problem that compromises the apartment itself. You can just simply clean this area and apply a cementitious parge coat or a flexible sealant like a polyurethane caulk to create a smooth line and prevent water from sitting in those little pits. That is a good practice for long-term protection against moisture and potential insect ways, not a structural necessity.
 
That rough edge is normal. When concrete hits the form edge, it never gets a polished finish. As long as the slab isn’t cracking or flaking, it’s fine. You don’t need to seal or fill it unless water is pooling against it or you’re worried about looks.
 
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