Mold Action Guide: What to Do About Toxic or Allergenic Mold in buildings: Step-by-Step Action Guide to the necessary steps to address mold in buildings, How to find toxic mold in a home, house, building, or office, how and when to hire an expert, how and why to test for mold, how to remove mold, how to prevent mold.
If roof leaks or attic moisture condensation due to a combination of inadequate attic ventilation and a building moisture source (wet basement, plumbing leaks, roof leaks) causes excessive moisture or actual wet conditions in an attic, conditions are ripe for extensive mold growth. Visible mold may appear on wood surfaces in an attic such as on rafters or roof sheathing. Hidden mold may be present and may be even more of a problem if it forms in insulation or in the ducts and air handler of an air conditioning or heating/air conditioning system. Mold from an attic can be a problem on lower floors.Typical building air convection currents tend to move air up and out from lower to upper building levels, so one would not think that much mold would move down from an attic into the living area. But important exceptions to this can quickly move problem mold from an attic into a living area.