Can I encapsulate AND waterproof crawlspace?

Old 03-24-15, 03:49 PM
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Can I encapsulate AND waterproof crawlspace?

My crawlspace gets too humid when it rains -- causing allergies in living area and hardwood floor to warp.

I've already put a french drain in it, which eliminated water puddles, but did not reduce humidity enough. I guess water table under the french drain still contributes humidity to crawlspace.

I had various contractors come to look at the issue. Some suggest encapsulation, some suggest a footing drain plus waterproofing foundation wall, since there is obvious signs of water intrusion through the foundation walls (efflorescence).

I heard that crawlspace should not be encapsulated if foundation wall is waterproofed from the outside, because this would trap water inside the wall. Is this true?
Old 03-24-15, 04:08 PM
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Foundation should have been waterproofed from the outside before the french drain went in.
Is there at least a 6 Mil. vapor barrier on the ground in the crawl space?
No drain tiles and a sump pump?
Old 03-24-15, 04:14 PM
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I likewise believe your solution would be waterproofing from the outside, landscaping away from the foundation, running downspouts at least 4' away from the structure. With those precautions you should have minimal moisture in the crawlspace.
Old 03-25-15, 08:36 AM
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Vapor barrier on the ground is a must.

Is this space open to the outside or to the house air?
Old 03-30-15, 01:19 PM
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saw something @ the apron store today - a POWERED foundation vent looks cool - hook that up to a humidistat & VOILA !

we regularly work in crawl spaces installing 20mm vapor barrier,,, think we have 35 to do in the next 2 weeks,,, code calls for NO fndn vents currently but they'll change their minds in the next few years as it seems to change every now & then.

personally i like vapor barrier on the dirt + up to exterior grade & that's what we do,,, above the vb, we install either xypex or masterseal 500,,, wet runs to dry however, IF you have an actively leaking crawl, you need to install sump + drain - either gravity OR pump

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