Mold

I picked up a large plastic storage bin that had been sitting in the same place for 6 months and found various spots of mold on the cement underneath it. The weird thing is that we have a very dry basement, in fact people comment on how dry and 'unbasementy' it seems. It was not near anything that would have been wet. What could have caused this and what should I do to prevent it. I have a humidity meter and it is never in the 'humid' section so I really can't believe I need a dehumidifier. Any suggestions? BTW I am not going to jump on the fear factor Brokivich bangwagon and get all excited about a little mold. We have been living with it since the dawn of time.

 

All concrete transpires moisture no matter how bone dry it may appear. The moisture became trapped under the storage bin. As mold/mildew spores are everywhere, the spores found a perfect breeding ground. They prefer dark, damp, unventilated, soiled surfaces. Disinfect the affected area on the concrete and the storage bin with bleach/water solution. A dehumidifier is helpful in basements to keep humidity levels down. There are penetrating concrete sealers available which will also minimize moisture problems.