Bathroom Mold- Stachybotrys

Several tiles around the edge of my bathtub shower came loose.  The wall material underneath was dark in color, and I suspected that was present.  A mold consultant took what he called a tape lift sample and sent it to a commercial laboratory.  The laboratory reported that it was heavily infested with Stachybotrys chartarum, the black toxic mold.  I have read that this mold is very dangerous.  I am afraid that if we stay in the house, my family will be at an extreme risk of being exposed and “poisoned” by this mold.  What should we do?-  Concerned, Everywhere, USA

 

            The situation you describe is a very common. Shower water often works its way through the grouting of bathroom tile.  Grouting often comes loose and provides small pathways for water to come into contact with wall materials behind the tile.  In houses built in the last two decades or so, this should not be a problem since many building codes require the use of a water-resistant greenboard behind bathroom tile.  Even in the absence of such code provisions, many builders used “greenboard” in such applications.

            Greenboard was not used in most cases in houses built in the 50’s, 60’s, and 70’s.  Over time one can expect that  water would have penetrated the grouting and wetted the cellulose facing of the gypsumboard on the other side with a resultant small infestation of mold that may in many cases include Stachybotrys.

            My guess is that such situations exist in hundreds of thousands of homes (houses and apartments) in North America.  That indicates that small and minor Stachybotrys infestations in North American homes are relatively common.  That means that in many homes Stachybotrys is present without any knowledge of building occupants and that for those who are unaware “ignorance may be bliss”.

            The presence of a few small spots of Stachybotrys behind bathroom tile is no reason for a family to leave their house and find shelter somewhere else.  In the short term one can isolate Stachybotrys by putting the tile back in place and securing it with heavy-duty tape until it can be remediated.  Stachybotrys isolated from the building environment behind bath tiles or isolated by covering with heavy-duty tape is unlikely to pose a mold exposure problem.

            In a recent case, a homeowner in removing loose bath tiles discovered Stachybotrys present on gypsumboard facing on the other side of the tile. 

The panic button was hit and they abandoned the house and first requested that it be remediated by their insurance company and then sued when the insurance company balked.  As expected, several years went by before everything was settled.  In the meantime the house went unoccupied with temperatures set only high enough to prevent plumbing from freezing. The cool/cold conditions produced elevated humidity levels that produced a significant mold infestation in the kitchen, dining area, and family room surfaces and greatly increased the cost of remediation. 

 

 

The occupants’ cat was given to a neighbor and as can be seen in these digitals “the cat came back”.

            The lesson here is that what should have been at best a $1000 or so remediation was turned into a $40,000 remediation with the family not being able (because of their fears) to occupy their home for several years.

November 11, 2005