Vapor Barrier

[Roger]

First summer in my new 3200 sq. ft. home. Manufacture instructions suggested putting plastic on the ground to keep moisture from rising from the ground to the bottom of the home. I gave a concrete block foundation with 22 vents around the home. Having alot of moisture being trapped on top of the plastic and collecting above on the plastic that secures the insulation to the floor. I have no water running under the home. We have had the most rain for the month of July in history. I think it is a air movement problem. Should I Remove the Vapor Barrier so the moisture can go into the ground instead of collecting on top of the Barrier.

[Charles Akers]

Hi Roger,

My wife and I live in The southern part of North Carolina and we have the same problem - accumulating moisture under the house.
We do not have a vapor barrier.
In what part of the country are you located, if you don't mind my asking?
We installed a fan, but that seems to have made the moisture problem worse by moving even more 90 + degree, 85 + humidity air through the crawl space.
As you said, we are experiencing a very wet summer.

Do you have central air conditioning? Do you have any air conditioning leaks in your ductwork? We suspect that we may have as the water seems to be accumulating more near some of our AC ductwork.

[Roger]

Charles, I live in northern Georgia and yes I do have central AC. My moisture problem is over the entire crawl space. I have removed some of the vapor barrier and it seems to help in those areas because the moisture does not collect on the bottom of the home. I guess it allows the moisture to go into the ground. I installed a second exhaust fan yesterday. I have two 2.5 X 2.5 access doors so I mounted the fans in the doors. I also thought about pulling in hot moist air, would it make it worse. I sure of one thing, if air is not moving through the crawl space it will never dry. I need some dry air to move through the space. My HVAC ducts are in the attic, my return ducts are in the crawl space, so I don't seem to have a sweating problem from the ducts.