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Yet More Basement Questions

1447 Views 8 Replies 4 Participants Last post by  DocWard
This may take a bit of explaining, so please bear with me. Our house sits on a south sloping lot, with attached garage to the north, and not a walkout basement, but full sized windows facing south. At the time of building, tar was sprayed on all of cement block that is under grade. Our basement slab is not attached to the walls, but has a small trench that runs the perimeter (floating slab design?). There is a drain in the floor itself, and another in the trench.

Our problem, the lot also has a few springs and the basement is damp, with dampness on the blocks, particularly the north wall, which is under the garage.

The basement floor has only flooded once since we built, and then it was only a small amount, after a very cold period. I have always thought it was because of possible ice build up in the drainage due to the cold.

I would like to finish the basement eventually, but it will be some time before money is available to do so.

I would like to do something in the interim so that the basement is more user friendly, with less dampness, mold and mildew. I have read good and bad about Drylok, and have seen concrete sealers referenced, but don't know any names or specifics.

While it seems the most often suggested action here is to waterproof from the outside with sealer, membrane, etc..., that doesn't seem a viable option for my north wall, either practically or financially.

So, are there any products out there that will work from the inside? Any ideas and suggestions are greatly appreciated.

Also, the questions about what happens later come up. Do I put up a vapor barrier later? How do I deal with the trench around the slab? I suppose those can wait, but I am trying to think ahead.
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This may take a bit of explaining, so please bear with me. Our house sits on a south sloping lot, with attached garage to the north, and not a walkout basement, but full sized windows facing south. At the time of building, tar was sprayed on all of cement block that is under grade. Our basement slab is not attached to the walls, but has a small trench that runs the perimeter (floating slab design?). There is a drain in the floor itself, and another in the trench.

Our problem, the lot also has a few springs and the basement is damp, with dampness on the blocks, particularly the north wall, which is under the garage.

The basement floor has only flooded once since we built, and then it was only a small amount, after a very cold period. I have always thought it was because of possible ice build up in the drainage due to the cold.

I would like to finish the basement eventually, but it will be some time before money is available to do so.

I would like to do something in the interim so that the basement is more user friendly, with less dampness, mold and mildew. I have read good and bad about Drylok, and have seen concrete sealers referenced, but don't know any names or specifics.

While it seems the most often suggested action here is to waterproof from the outside with sealer, membrane, etc..., that doesn't seem a viable option for my north wall, either practically or financially.

So, are there any products out there that will work from the inside? Any ideas and suggestions are greatly appreciated.

Also, the questions about what happens later come up. Do I put up a vapor barrier later? How do I deal with the trench around the slab? I suppose those can wait, but I am trying to think ahead.
If it helps; my inside is completely drylok'ed (previous owner) and I had drain tile installed by basement systems. My basement is still a never ending battle. I'm running two dehumidifiers 24/7, just to keep humidity ~60%

The water will eventually push right through; the drylok will make the basement look nice long enough to sell it (sigh).

IMO; based on my horrible experience; feedback here; books from the library; Holmes on Homes, This Old House, and other internet research, waterproofing has to happen on the outside with a proper drain at the base of the foundation (sitting on footing or next to it; I'm still trying to figure that one out); mastic tar; then felt; then mastic tar; then dimpled membrane. Run the drain to your sump or away from your property.

I am not in the exact situation; I have a detached garage and a walk-in. But my property is southern sloped and eastern sloped.

Whatever solution you choose; please share your results!
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I have to be honest, a lot of that is way over my head. It will take several readings for me to figure it out.
The whole site he linked has TONS of info though...

http://www.buildingscience.com/resources/more-topics/homeowner_resources
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At least some of it makes sense.
I don't really know where the water problem is coming from, but iuf its due to any standing water problem, then look up "french drains"
I don't really know where the water problem is coming from, but iuf its due to any standing water problem, then look up "french drains"
Not standing water so much as it is high water table and springs, I think.
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