"badgolferman" wrote in message
...
RogerT wrote:

"badgolferman" wrote in message
.. .
It seems there is condensation building up underneath my house on
the end near the garage that doesn't have foundation vents. Some
of the joists have mold or a fungus on them. .....

I recently went to a meeting where an inspector talked about this
condition. He suggested no insulation between the joists or, if there
is insulation, to make sure it is unfaced insulation. ....

My house is in SE Virginia near the Chesapeake Bay. We do not have
basements in this area due to the high water table. The humidity is
high in this area. I have a moisture barrier on the ground and
insulation between the joists. The insulation has backing on the side
that touches the subfloor.

I think the problem may be that, in your high humidity area, and with
between-the-joists insulation that has any vapor barrier (even though it is
on the correct side), you are trapping the humidity in the crawl space where
it can cause moisture and mold on the floor joists. And, since the outside
air is humid, the fans don't change that. If anything, the fans may be
bringing in humid air from the outside and just adding to the humidity (and
condensation) in the crawl space. You already have a vapor barrier on the
floor, which is a good thing. When someone described a situation similar to
yours at the meeting/presentation that I attended-- with faced insulation
between the floor joists -- the inspector's recommendation was to remove the
insulation altogether. Removing the insulation, in his opinion, will enable
any moisture in the crawl space to dry out. Keeping the insulation
(especially with the facing still in place) keeps the moisture from being
able to dry out.

This home inspector is also a licensed structural engineer (or something
like that -- I forget the exact engineering title/license he has). Based on
everything else he said at the meeting, and the number of years of
experience that he has, I was confident that he knew what he was talking
about on this crawlspace moisture issue.

I moved a fan from the porch area to the area that builds up
condensation and aimed it toward the other side of the house that is
dry and has a fan too. That fan blows toward the foundation that has
vents. The fans have been running straight for three days. Hopefully
it has dried out enough to remove the condensation by now.

I think I will call the company today and have them perform the
spraying that kills everything.

I think that the disadvantage of paying a company to spray now is that it
doesn't correct the underlying problem and the mold will come back.