Kevin wrote:
I have a crack - expansion joint - in my shop concrete floor that extends to
the outside underneath the exterior wall ( I can see daylight from inside
the shop)

The pesky ladybugs, etc like to line up and invade.

The crack is about 3/16" wide.

What's a good way to fill/seal this?

One of the flexible, self-leveling concrete patching/sealing products
would be my choice.

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