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Water/moisture under new 6 ml membrane in crawlspace?

9 years ago

Several weeks ago, I worked with others to install 6 ml vapor membrane over dirt crawlspace, advancing it up concrete walls about 6 inches and securing it. Because of a pending cinder block repair at the entrance to the crawl, I left a 3 ft gap uncovered along the original foundation wall. It has not rained that much since this went down.

Today while in the crawl space (now has lights, yeah), I lifted the vapor barrier membrane and saw considerable moisture on the undersurface. The ground was not muddy, but it too was wet.

Should I have waited to install this membrane until the ground of the crawl space was less moist? I'd be waiting a long time in our humidity, even with opening the outside vents instead of closing them (which I'm doing now to create a more conditioned space). Could that lack of full ground coverage (i.e., that 3 foot gap) be contributing to this problem? There is no pooling/moisture on top of the vapor barrier, it's just underneath. The crawl space walls are very cold, and I think water may be wicking down between the CMU blocks towards the ground.

I'm very upset at seeing that amount of water under the membrane, mainly for what it could promote. I do realize that that this water previously was present in the crawl air as water vapor. I have dehumidfiers running at the crawl space entries.

I'd appreciate any comments on if this is normal or if I should remove the 6 ml ground barrier (doubtful). By conditioned space, I mean closed vents, supply and return grille from hvac running through, insulated walls , doored entry etc. I Have not figured out what to put on the floor ceiling between joists: foam or cellulose seem 2 options-any thoughts?

Thank you.

This post was edited by SparklingWater on Sun, Sep 7, 14 at 17:08

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