Vents causing dripping moisture in crawl space?

Discussion in 'Homesteading Questions' started by elizabeth-s, Nov 28, 2006.

  1. elizabeth-s

    elizabeth-s Member

    Jul 11, 2002
    (Hubby here using wife's login)

    In a post about termites, my wife mentioned the newly added vents in our crawl space and how I believed they caused more moisture. Many responses stated that vents should reduce moisture.

    Before we had vents, our crawl space was cool and clammy, but dry. After the vents (which open in the summer, close in the winter), everything now becomes covered with beads of dripping condensation in the summer. My take is the hot, humid air comes into the crawl space, cools, and condenses on everything. There are beads of water everywhere. In fact, the reason I discovered this is because the moisture shorted out our phone lines in the junction boxes. I had to seal all phone connections in waterproof wire nuts (wire nuts with a gel inside them) before the phones would work again. All the electrical boxes are also rusting out. Then the mold started growing, which looks like white spiderwebs. I keep it a bit under control by spraying a diluted bleach solution on the mold, which appears to help, but I have to do this every year.

    I'm thinking I need to seal up the vents so the humid outside air doesn't get into the crawl space. The crawl space is quite cool even in the heat of summer. However, our termite inspector is the one who recommended (and installed) the vents in the first place, and I would assume that other crawl spaces in this area would have the same issue. Why would he recommend something that made the problem worse?

    Does anyone else have a vented crawl space with this problem?

  2. littlebitfarm

    littlebitfarm Scotties rule! Supporter

    Mar 21, 2005
    My problem wasn't that bad. I sealed my vents. The entrance opening is now through a closet floor. I stuck a dehumidifer down there and stuck a small fountain pump into the water container. A hose from the pump goes to drain pipe. The pump is plugged into a switched outlet in the closet. Now the crawlspace is nice and dry and I don't have to go down there!!


  3. TNHermit

    TNHermit Well-Known Member Supporter

    Jul 14, 2005
    East Tenn.
    IF you have a crawl space and you don't have plastic down on the ground more than likely that's your problem. Moisture wicks up from the ground and the cold air coming in the vents even when closed causes condensation. But you need the vents
  4. ttryin

    ttryin Well-Known Member

    Apr 10, 2005
    Go to and read about venting and not venting crawlspaces in your geographical/weather area.

    Good luck.