How to repair the concrete sill under our front door?
We’ve been having some issues with water leaking into our basement under our front door. We have a metal threshold over a concrete sill, and our front porch is a concrete slab about 4’x6′. There are a number of weatherproofing issues we need to address, but the most urgent is the concrete sill under the door which has been crumbling for a while and presumably is the source of our leak. I’ve removed the threshold and cleared out most of the loose concrete so I could see what was underneath. Here are a few photos:
Now that I can get a good look, my best guess is water was entering the house along the black tar paper, and not a crack as I had first thought.
Given the porch is level and roughly flush with the subsill (the darker concrete in the photo), I’m not quite sure how to properly fix this. I can pour a new concrete sill, but water is just going to sit along the seam and eventually (I assume) break down the concrete in a few years. What’s the right way to fix this?
Any advice would be much appreciated.
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