Hi. I am a homeowner with a Wisconsin home that was built in approximately 1930. That said, it has its issues and I have been working to do proper maintenance and care with updates and renovations (including a complete gutting to the studs in the whole house, re-insulating,rewiring, plumbing, etc.) with the mindset that it would be our ‘forever home’.
When we purchased this home, we moved from a home in another area of the county with sandy soil to an area that has almost 100% clay soil. We also moved from a home with one bathroom, but after having our second daughter, we quickly realized that a second bathroom in our home is a necessity. So after some consideration of different building options, we decided to put in a 3/4 bath in the basement. (Lav, shower, toilet)
Now my ideas of a basement bath are different than most home owners. I am not looking for anything beautiful, I require only that it functions as a bath. In short, the space is going to be only minimally finished with as many inorganic materials because I understand that a basement is a basement. Other than a coat of paint,I wasn’t going to cover the block at all except for where the shower is, and where I used whatever type of membrane to drain the block to the french drain. Our basement is primarily used for storage/our utilities area/workshop/study area (I am in an industrial maintenance apprenticeship).
I had an area of the basement were there was formerly a cistern. In front of that cistern was a floor drain that the DWV plumbing used 4" clay, and the trap for the drain was cracked (presumably from a prior homeowner removing the cistern). Because there was occasionally water that came up through the broken elbow in the floor and we had thoughts of replacing it. We also wanted to cut out the floor of the old cistern and bring it down to the same level as the rest of the basement floor to avoid the tripping hazards.
I give all of that background to kind of present the logic behind our thoughts for the placement of this bath. The other reason is that it makes it easier to tie into the vent system for our home. In a sense, we are killing a few birds with one stone.
Anyway, I have been working on it in my spare time and as we can afford it after pulling the permit last spring. So far, I have the floor cut out and dug, I have an interior french drain installed to the sump pump with 4" perforated pvc pipe to deal with the moisture under the floor of our home along the wall where the bathroom is going.
The main issue I have been dealing with since, is a solution to drain the block wall. Our home is built on a monolithic slab. The one wall has a baseboard drainage system that is adapted to the sump, but that ends before where the cistern began. I don’t have moisture problems in that area of the house, but I do have them where the cistern is. The block is seeping water to the surface and because the wall is double thick in that place, I am assuming that both courses of the block are filled.
The second inner course of block for the cistern wall was placed to the inside of the thicker area of the monolithic slab that was poured for the footing. It looks like a previous homeowner may have tried to remove some of the block for the adjoining cistern wall, but stopped. I am not interested in removing it, because I believe it is helpful to the structure of the foundation. But this means I now have to get the water out of both courses of block.
After reading though some of the comments and other information here regarding basement waterproofing, I really thought I would seek some input. I hadn’t really anticipated the water in this area to be as significant as it is, and I am always interested in doing things right the first time. Would it make more sense not to drill weep holes or run weep tubes to the inside underfloor perforated pipe, and just dig along the outside of the foundation, sealing the block from the outside, possibly putting in a drain around the outside perimeter to the back yard (our whole yard is on a pretty consistent slope from the street to the back yard)?
The water problem is primarily only on the driveway side of the house. It is concrete, and it does appear to be sloped away from the home, the soil grading between the house and driveway also seems to be proper. It probably starts close to 4’ wide (between house and driveway, coming from the street) and tapers down to tight against the foundation at the back of the house. This side of the house probably has a wall that is close to 35 feet long.
To the best of my knowledge, the outside presently isn’t sealed at all and there are no outside perimeter drains along the foundation existing, and the clay makes for lousy drainage in general. (I have no idea what was considered acceptable building practice that long ago.) I should also mention that I am slightly concerned with radon gas as our area is known for it, but I have not yet had our home tested.
If I do drain the block to the inside of our home, being that the slab is monolithic, what kind of membrane/tray would be suitable to seal off any potential issues with gases, resist mold and mildew, and not be much higher than a baseboard?