On 9/27/2011 12:45 AM, 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. The prior owner installed some
crawlspace fans and had them on a timer. I went under there today and
moved one of the fans from under the porch to that wet area and aimed
it toward the other fan that was blowing in the direction of the vents
at the other side of the house. I had to run a new wire from the old
location to the new location of course. I've left the fans on
continuously and will check it in a few days.

The exterminating/moisture inspection company that told me about the
problem has offered a $560 treatment that sprays all exposed wood under
the house and kills any thing that is alive now. I've considered going
under there and spraying bleach/water solution, but I don't think I'll
come out alive.

Does anyone have experience with this?


It would probably help to know where your home is located to get a
better idea of the climate in your area. Also, is there any insulation
between the joists (with or without facing)? And, is it an uncovered
dirt floor in the crawl space, or some other type of floor?

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. He said placing 4-6
mil plastic on the dirt floor can create a moisture barrier to help
prevent the moisture in the soil from coming up. And he said that
sometimes no vents are better than having vents because the warm humid
air from outside can come in through the vents and cause the
condensation you are seeing -- especially if there are fans operating
which bring in the humid air.

Back in stone age when I grew up, crawlspace vents were SOP, and
visqueen was still an exotic product. There was some accepted practice
for when to open and close them, but since the handles were on the
inside, nobody ever did. Fuel was so cheap, nobody cared. I still
remember being in single digits, being drafted to ferry insulation
across crawlspace and attic, where grownups fastened it into place, and
seeing the stripes and bare spots on roofs when heavy frost or snow came
along. Haven't seen crawl vents on new construction in decades. Not
that crawls are common here in basement country, other than on modular
and starter houses, but insulated foundation walls and double-plastic
dirt cover are the current practice, which almost brings the crawl
inside the heated envelope, since a deep crawl will never freeze hard
due to ground heat and house leakage.

When I hit the lotto and build my dream house, I'll pick location
carefully so water table won't be an issue, and put in a deep
super-insulated basement, to get that free heat and cooling from being
linked to the ground temp below frost line.

--
aem sends...