THE STEALTHY  MOLD SOURCE

    Foundation ventilation is a good idea and is also a building code requirement.   Vents are installed in homes so that air can pass beneath the floors and dry out any residual moisture that accumulates,  especially during  winter.   Particularly in the mountains, people want to stop freezing air from accumulating under their homes.   This is done to keep heat from escaping and helps protect plumbing.  However, when beautiful spring weather arrives again, all too often owners forget to reopen these vents.

     This results in moisture being trapped in sub floor areas with no cross air flow to dry it out, thus allowing mold to inevitably form.   Some homes have not had ventilation in the sub floor areas for years.  When a home such as this is finally checked for pest/fungus problems, usually at the time of sale, mold is discovered.  It’s hard to say with accuracy just how many homes fall under this category but our educated guess is 20% to 25%.   

    Newer model homes usually have little levers on the outside of the foundation vents that make it easy to close off the vents in winter and open them again in summer just by moving the levers up or down..  Older homes without levers may require a trip under the house or, covers installed from the outside.  With the newer style vents it only takes one trip around the home before winter sets in and again in spring.  In some cases it may make sense to replace the vents with the newer style.

           In an easy repair, the mold is usually mitigated by scraping the mold off of sub floor beams and spraying with a fungicide.  However,  if mold has had a long time to grow, it could require expensive replacement of materials.