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How to fix bottom of walls from getting damp?

BirdMelt95 | Posted in General Questions on

I recently bought my first house and have been living in it for about a month. The house has a four seasons room in the back that was an addition, not sure when though. The walls are wood of some sort, on exterior and interior. When I had the house inspected I was notified of this and figured I could fix it myself, but there is no protectant or anything for moisture and such so the bottom of the walls in some areas are wet and showing on the inside of the room, as well as getting the floor damp. Is there anything I can do for a quick fix to help the situation for now and get through winter? And also what could I do as a long term fix?

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  1. GBA Editor
    Martin Holladay | | #1

    1. Lower the exterior grade, which should be a minimum of 8 inches lower than the lowest wooden components of the house.

    2. Modify your roof to create wider roof overhangs.

    3. Install gutters at your roof eaves.

  2. joenorm | | #2

    I am guessing roof overhangs is the only way to accomplish this

  3. BirdMelt95 | | #3

    I have gutters and a decent roof overhang, my issue is there’s nothing between the base of the exterior walls and the ground around it so it’s constantly damp, or right now wet because of all the snow and it melting and what not. I live about 45 minutes from Chicago so right now we have a decent amount of snow. Is there anything I can do to stop that base of the walls from getting wet and protect them at all? Dig around the walls and put something there, or anything like that? Thanks for the replies

  4. Expert Member
    BILL WICHERS | | #4

    Presumably you could excavate along the bottom of the walls a bit to create an artificial low point to keep the wood parts of the wall away from water. You'd really need a french drain in that low point to keep it from filling up over time though. Filling it with clean gravel may help too.

    A sort of long term bandaid might be to put a wide PVC trim board along the base of the wall and seal it as a sort of "house boat" to keep water off of the lowest wood parts. The PVC board won't care if it gets or stays wet, but the risk would be that you might trap some moisture inside the wall since chances are you'll never get it completely sealed so it's always likely to have some small leaks here and there.

    Your best permanent solution is to improve drainage around the perimeter of your home, and lower the grade a bit if the wood structure is particularly close to the ground.


  5. the74impala | | #5

    Is this on concrete? If so, could you open up the inside until spring, allowing it to dry faster, then address the drainage issue that is likely present? You might want to get a moisture break, like sill sealer under the bottom plate for any moisture coming from the slab.

  6. walta100 | | #6

    To my mind the first unanswered question is, where is the water coming from?

    The roof could be leaking.
    The windows could be leaking
    The grade may be so high that water is running indoors.
    The windows may have aluminum frames that water is condensing on.

    Every one of the problem on my list had a different solution.

    All too often 4 season rooms start life as a patio one owner at a time brings the patio a little closer to being a room. Then it turns out there is no permits for anything there is no footing, no foundation, no waterproofing, no insulation, no electrical, no heating. In short it is just a pile of one mistake on top of another mistake.

    I hope for your sake this is not the case. Short of having a contractor look at what you have we are all just guessing.


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