According to our elderly neighbors, our basements flooded for the first time in 50 years after a month of nearly constant rain. However, that leads me to this question.
The basement floor is sloped so each half pushes water to one of two drains. The drain I'm concerned about is located behind a wall with a cement block base. There is a small hole at the base to facilitate water flow. There's also a slight depression on the floor running the length of the exterior wall.
I'm planning on building a bonus room along these walls. The plan is to glue 1.5 inch rigid insulation against the exterior wall and butt the stud wall against it. Then insulate with unfaced fiberglass. Any problem with that plan?
The main question is what should I do with that depression, the insulation and the wall? I think the possibility of flooding again is very low. Should it happen, having a gap behind the wall leading to the drain would be very helpful (and accepting the fact that clean-up will likely involve demo and rebuilding). However, I can see all sorts of problems coming up with that depression on the floor and leaving space like that between the floor and wall.