The shop floor at our new place sweats. Not sure if the floor doesn’t have a vapor barrier or if it’s from the micro climate we live in, or both. It’s very common to have dense fog all day in the summer with NE winds from the lake.
The humidity in the shop got so bad that some fabrics on certain gear started to grow mold (the seats on my Otter shacks, various backpacks, clothing, etc). Some did textiles were fine, while others weren’t.
Fans and opening windows on nice days helped some, but overall the humidity was still too high (70%+)
A few weeks ago I plugged in a portable dehumidifier in the middle of the shop and have it ran into the floor drain. It completely cured my problem. It cycles on and off as needed and keeps the shop at a consistent 55%
No more damp floors or mold.
Nice. Might have to do the same. Wish I had a floor drain.