Hi

My basement smells, well, basementy, when things are very humid, or it's been raining. Not moldy or mildewy or rotten, just not very good. There is no water leaking anywhere I've seen.

This is most noticeable in the unfinished side of the basement, and when the fan from furnace or A/C hasn't been running.

The basement is poured concrete, about 60 years old. At one point there was an oil tank down there and the floor is discolored - maybe there was a leak there at some point? The smell, however, isn't like oil, either. It's just dank. Because it's a small house, the smell is also noticeable upstairs unless the air is circulated.

I'm hoping that I'm just paranoid because everyone is so hyped about mold - is it okay for an old basement to smell like an old basement? :)

Is there a way to mitigate this? I'm not sure if running the furnace fan 24/7 is very efficient or economical. I do have a dehumidifier down there, set at 50% and its NOT kicking in all the time, so the humidity level is only an issue during rainy times. Could this be just damp concrete?