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Community and Q&A

Moisture & mold

Justsimu | Posted in General Questions on


We have a high humidity and moisture in house.

Can gap in caulking causing the shower water to leak into crawl space and cause high humidity in the house.

We recently got a new washer and dryer so suspect that is the cause. But plumbers have ruled out any pipe leaks. We are not able to detect the source of water and everyone says gradual water seeping into crawl space can’t cause moisture n mold. It has to be a lot of water. Is that true.

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  1. Dana1 | | #1

    Local climate can affect what the more likely & less likely causes are. Where are you located?

  2. GBA Editor
    Martin Holladay | | #2

    If your house has elevated indoor relative humidity (RH), a poorly caulked seam in your shower is unlikely to be the cause of the problem, since the amount of water that could get past the crack is relatively small.

    That said, if you suspect such a problem, you should investigate the shower problem and fix the leak. You should also make sure that your bathroom has a good bathroom fan that operates well, and you should use the fan regularly.

    If your crawl space is damp, the usual source of the moisture is the soil near your house. Moisture in the soil may be keeping your foundation walls damp. Moisture can evaporate from these walls, and from your crawl space floor, into your house.

    For more information on these issues, see:

    Fixing a Wet Basement

    Building an Unvented Crawl Space

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