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House Crawl Space Question

Discussion in 'Road Side Pub' started by mysticsvt, Aug 23, 2019.

  1. mysticsvt

    mysticsvt southernmustangandford Premium Member Established Member

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    So we've been in our "forever" home for about 3 years now. I think I need to address the 3' crawl space this house has. The insulation is sagging and pretty much destroyed. Would installing a 10+ mil plastic sheeting on the dirt and re-insulating the flooring be the correct path to take? Live in South Carolina, 30 degrees - 100 degrees mostly. Great drainage around the house as we installed a French drain a year ago but still damp under house to a degree. I refrain from insulation due to the moisture. Any thoughts greatly appreciated, not my area of expertise. -Shane
     
  2. HillbillyHotRod

    HillbillyHotRod Hooligan rabble rouser Established Member

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    Putting plastic down will help. We did that and it is not damp under there. We do have vent that we open in the summer and close in the winter to keep it aired out. There is no floor insulation.
     
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  3. ashleyroachclip

    ashleyroachclip Well-Known Member Established Member

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    That is how i do it .
    Required plastic thickness here is 6 minimum.
    There is a mesh that can be applied after new insulation, that keeps it in place .or an easier method is the wires that squeeze between the joists .
     
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  4. jshen

    jshen Well-Known Member Established Member

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    Consider sealing in your crawl space! I am in Savannah and it was a great move for me. I had a contractor lay 10 mil plastic on floor, all posts and vents complexly sealing area. The installed a dehumidifier that keeps humidity at/below 50%. The effect was to not need insulation, lower energy bill and keep rodents out.
     
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  5. GodStang

    GodStang Well-Known Member Established Member

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    On my fathers house, also in South Carolina, when we built it we put plastic through the whole thing, new insulation and he has a dehumidifier down there for when it gets bad.
     
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  6. mysticsvt

    mysticsvt southernmustangandford Premium Member Established Member

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    I did an estimate at one time for insulation but at 15K it was a little steep. I'm still paying off a 10K AC install. Home ownership is one thing after another I swear.
     
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  7. jshen

    jshen Well-Known Member Established Member

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    Way to much! I did 2700 sg ft for less than 1/2 of that. I have bond on the work and the company checks humidistat every year. I have a gauge on my desk here that shows temp and humidity in AND below house in crawlspace.
     
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  8. mysticsvt

    mysticsvt southernmustangandford Premium Member Established Member

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    I meant to say a full encapsulation, sorry.
     
  9. jshen

    jshen Well-Known Member Established Member

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    I took it at full encapsulation which is what I did. For what it's worth I also fully foamed the attic area as well....I pay less for energy than I do cable tv. As hot as it is right now- my gauge reads crawl space at 76 degrees and 52% humidity..
     
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  10. mysticsvt

    mysticsvt southernmustangandford Premium Member Established Member

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    Yeah the attic is another thing I want to hit. It's literally bigger than my last house and hot as hell in the summertime.
     
  11. wundrbird

    wundrbird Proud Father Established Member

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    I'm with the others on encapsulating the crawl space, but for less money just a new, sturdy vapor barrier on the ground and a good dehumidifier will probably work well. Make sure rain water moves away from the house, close off the vents, and you're done. Like a previous poster said, you may not even need insulation at that point. The worst thing that architects and builders in the south ever did was to have a vented crawlspace and an air-conditioned home. That's the perfect recipe for mold and termites.

    Start here for some good info:

    Mold/Moisture

    Look up radiant barriers for attics as well. That's the second phase soon to come in my home.
     
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