Well, after about 15 years of debate, and putting it off, I finally pulled the trigger on dehumidifiers in my crawl space. A few years ago I layed a new vapor barrier, which helped a lot. I was always of the opinion that a house needs to breathe. Well, in the summer, with the humid air mixing with the cool air under the house, that caused big problems in July aug and sept. Things stay pretty dry in the spring, fall, and winter months.
This year I cut some foam board and sealed the vents, and installed two dehumidifiers, one on each side (it’s separated by block with two small openings). They both drain to a sump pump. I went with the Alorair hdi65 model. They cost about $700 each. They each ran for about 7 days straight before getting it below 60 percent, and now it’s stabilized with them cycling on and off throughout the day. Man what a difference
! It is now dry as a bone under there. Now, I did not encapsulate completely, just sealed off the ground and the vents, which seems to have been quite sufficient. I plan to turn off the dehumidifiers in the fall and winter, and unblock the vents (they open and close automatic according to temp outside), to allow ventilation during the non humid months, when it naturally stays dry under there.
I’m amazed at how much of a difference this has made. I used to have wet insulation, wet joists, and puddles on my vapor barrier in the summer. Everything has completely dried up. I’m hoping the electric to run them is reasonable. They are both 120v. In total, with installing a gfci breaker in the box, and new outlet in the crawlspace, I have about $2k in the project. If the dehumidifiers hold up, it’s well worth the money in my opinion
This year I cut some foam board and sealed the vents, and installed two dehumidifiers, one on each side (it’s separated by block with two small openings). They both drain to a sump pump. I went with the Alorair hdi65 model. They cost about $700 each. They each ran for about 7 days straight before getting it below 60 percent, and now it’s stabilized with them cycling on and off throughout the day. Man what a difference
! It is now dry as a bone under there. Now, I did not encapsulate completely, just sealed off the ground and the vents, which seems to have been quite sufficient. I plan to turn off the dehumidifiers in the fall and winter, and unblock the vents (they open and close automatic according to temp outside), to allow ventilation during the non humid months, when it naturally stays dry under there. I’m amazed at how much of a difference this has made. I used to have wet insulation, wet joists, and puddles on my vapor barrier in the summer. Everything has completely dried up. I’m hoping the electric to run them is reasonable. They are both 120v. In total, with installing a gfci breaker in the box, and new outlet in the crawlspace, I have about $2k in the project. If the dehumidifiers hold up, it’s well worth the money in my opinion
Dew points of 80 degrees or more are regular. That leads to condensation on the outside of our windows!! Rh of the crawl space I saw hit 94%!!
