Black, wet spots on floor
We have noticed that our wood floors on the first floor are really darkening in spots where there was previous water damage. We bought this house (built 1955, Westchester County, NY) in 2006 and had the floors refinished before we even moved in. Right outside the bathroom door and in the livingroom there were spots that the floor guys couldn't remedy. Now, those very spots are super dark and damp. There is no evidence of any plumbing issues, nor is there any evidence of water leaking through the ceiling and we do not have pets. Could it be the extra humid weather that we are having? Should also note that in the fall we had a new boiler installed that leaves our basement about 30 degrees cooler than this time last year so the floor is actually cooler now too.
Could the humidity really be doing this or should we look into something else? Does anyone have instructions on how to fix it? Would just putting down a rug be bad?