Before we get into mold issues we should discuss what may look like mold but is not. White crystal material found on basement blocks or concrete floors is not mold.  Efflorescence  is a mineral accumulation sometimes indicative of water pressure pushing through the block.  Since concert and concrete blocks are non-organic materials, mold will not grow on these surfaces. The main cause of mold in Northern Ohio is due to basement floors existing as a cold surface.  The floor is located below the frost line (the frost line starts at 36 inches down from the dirt surface) and the ground is warm enough not to freeze. For this reason, buildings are built below this level to insure the foundations won’t heave or move due to seasonal freeze cycles. Below the frost line the earth maintains a constant temperature of 57 degrees. Basement mold growth is mostly a summer issue. During the summer the warm moist air finds the cold floor and condenses, then it evaporates and goes up.  The moisture starts the mold growth process on the basement walls, floors and ceilings.  Without a dehumidifier mold can grow within 24 to 48 hours.This includes a flooded basement. Some homes have mold that was brought in by the builder  who provided lumber at the time of construction. The mold generally is not toxic but is unsightly.  The mold generally referred to as “builder mold” is commonly  Cladosporium or Basidiospore molds that can be allergenic but  don’t produce toxins.   Generally we find more  toxic molds in basements versus the attics.  These molds include Aspergillus / penicillium and often Stacybotus “The Black Mold”. You are likely to find harmful molds from water issues that remain unresolved for long periods of time. These issues can be the result of flooding, hot water tank leaks, furnace a/c condenser pipe leaks, pipes bursts, kitchen ice makers and, water line leaks. The most common issue however is from not running a dehumidifier. If the ceiling tiles in the basement are drooping or the ceiling tracks have rust this may be indicative of moisture and in turn a mold issue. Mold professionals can’t see behind drywall or under carpet but signs of water can often be found on soft materials where damage is seen behind or under these items.  It often makes sense to test for mold behind these areas because basement mold types tend to be more toxic than attic mold.  Unlike attics that we have less contact with and airflow is present, basements have a direct impact on our everyday life. The Basement is an area where your family spends the most time. It may be a place your kids play, you work, workout, or do laundry.   Most houses have a forced air furnace. This means that air from the basement goes through the duct system and then circulates throughout the home.  This pushes mold throughout the entire home.  We recommend a furnace and duct cleaning with sanitization when mold work is completed in the basement . If the attic and basement are areas that don’t get a lot of attention, mold can go unnoticed but should  be cleaned and treated once you have the facts.