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Dirt Basement floor

I have a basement with a dirt floor and a field stone foundation. The basement his humid and smells extremely musty which permeates through the floor to the living room. I have tried laying down plastic and running a dehumidifying but I feel I am only dehumidifying the earth since I can't get a seal where the wall meets the floor. I was wondering what my options are?

Someone mentioned to pour a rat slab, about 2" thick. I have plenty of head space so I can afford to lose a couple of inches. Then run a dehumidifier. But will I still have moisture issues due to the field stone?

Can I just spray foam the basement ceiling? Essentially sealing the smell off from the rest of the house?

Should I do both?

Any help would be appreciated.


Re: Dirt Basement floor

I would think that improving venting in the basement/crawl space, in addition to the dehumidifier, should help a lot. If you pour a slab, do so over 6mm plastic sheets. Sealing the stone footings will help too.

Re: Dirt Basement floor

There isn't a really easy fix this. We had this problem in our own house: dirt floor basement, and while our walls are concrete, they were extremely old and seeping. Given the age of the home chances are there is not any proper drainage around your home. Obviously, this would be a huge step: excavating, installing proper drain tile, fixing cracks in the foundation etc... however, also an expensive measure.

So the next "best" thing, is to seal your interior foundation wall. Plug any major cracks/holes with hydraulic. Then, invest in UGL Waterproofer and paint the interior foundation walls. This will take 2 good coats, and depending on the size of your basement cost probably around $300-500. We noticed an immediate improvement once we coated the interior walls.

Your next step is probably debatable by some. Do not waste your money pouring a 2" slab that will crack and leak over time with use. It is not that much more to go ahead and do a full 4" slab. However, if you don't want to pour concrete at all, you could lay down poly (min of 6 ml), and then cover it with a thick layer of sand or crushed rock (more expensive, but less tracking through the house). Also, make sure you run your poly up the wall a distance, and seal it off with acoustic.

Those measures will certainly help control the humidity/smell. What do you have for ventilation in the basement? Are there any windows at all?

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