Finishing 100 yr old basement with minor hydrostatic water issues
This is my first post here- My husband and I own a 100-year-old home in St. Paul,MN (lived here 5 years). Our basement was cosmetically finished around 1970 (walls, ceiling, but NOT the floor). We'd like to make it an even better living space and update it, and finish the floor, but we are concerned about how to properly deal with potential water issues.
We have witnessed some minor, seasonal water seepage from the floor and we think the problem is mainly hydrostatic pressure. Some years there hasn't been any water at all.
The foundation walls are 19-inch thick limestone, which is in really good shape. The floor is about 2 inches of 70-year old concrete. We do have adequate headspace and an egress window already.
Here is what we have considered:
1) Installing drain tile
2) Sealing the floor and/or walls with a product like Sanitread (though we're worried that sealing a limestone foundation won't be good in the long run).
3) Repouring the floor, reinforcing it and making it thicker, and with modern cement additives that will help make it resist water and give it resistance to hydrostatic pressure
4) Not finishing the floor, so water can seep , and dry out if needed (the least interesting option to us)
5) A mongo dehumidifier (*we already use a small one*)
We have already landscaped properly around the house, and we have long gutters, etc
We would like to solve this problem from the inside- Digging on the exterior is out of the question cost-wise.
Can any of you recommend what options (or combinations of options) might be best- and things we haven't thought of?
Also- if you have any suggestions on how to heat the space efficiently (it's currently got 1970's era electric baseboard heat)....
We're pretty handy and have done a lot of work on the house so far- we're not scared of work (like taking out the floor and re-pouring it). We just want to make the right choices and only have to do this once. We know mold is a terrible problem to have, and that's the last thing we want.