Last summer we remodeled the basement; we waterproofed the exterior stone walls and put drain tiles at the foundation on half of the walls. When we did the back of the house we also replaced the steps going into the basement and redid a concrete patio. I did not waterproof the back wall because I thought the patio would do the work. After a few months, we had a small leak coming in between the door jam and the stone. It was coming from behind the new concrete wall, traveling through the mortar in the stone, and emptying both outside the door and into the basement. On the outside, the water has washed away much of the mortar around the stone. I initially tried to fill the space of washed out mortar with hydraulic cement, but it didn’t stop the leak into the basement. I ran water along the patio and figured out water was going through a hole in the expansion joint between the patio and wall. I sealed the expansion joint with a self-leveling urethane crack & joint sealant, which solved the problem for a time. I ended up drilling 3/8" drainage holes through the concrete wall to give the water someplace else to go. The water doesn't come inside as much, but I still notice water coming through the stone in between the door and wall. My next thought is that the water is coming from the ground, going under the patio to the wall. I'm planning on digging a drainage ditch around the patio so that it doesn't go under the patio. But I also feel like I can be trying different solutions all summer. Any thoughts on what else could be going on?