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Fix rotted wood where it meets concrete slab

rjoslin55 | Posted in General Questions on

My 2-story home is 14 years old. There is gravel drainage rock around most of the outside since there are no gutters. I was digging around and raking back some of the rocks and discovered that there are rotted 2x4s all along the outside, with bolts every 4 ft or o. . There is white foam between the rotted boards and the slab.  Can I just dig out and replace the rotted boards?

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  1. Expert Member


    The 2"x4's are your bottom plates connected by anchor bolts to the slab. They are what your house sits on, so you need to replace them in sections making sure that the walls are temporarily supported while the work is done, and they should be replaced by pressure-treated material.

    If you can see the bottom-plates that probably means the sheathing and siding has rotted away too, and will need replacing. The sheathing should be cut back high enough that the replacement pieces can be nailed to both the new bottom-plate, and the existing studs. That connection is what keeps your house from blowing away in high winds or earthquakes.

    The problem will re0occur unless you do something about the splash-back from the water running off your eaves. You need to install gutters, slope the ground outside the house away from the foundation and keep grade 8" below the bottom-plate.

  2. Expert Member
    BILL WICHERS | | #2

    +1 for installing gutters. Gutters will help a lot with moisture problems around the foundation. I’d also install a capillary break between the new bottom plate and the top of the foundation while you’re replacing the rotted wood. You should be replacing that rotted wood with new pressure treated lumber too.

    Check that the ground around your house is sloping away from your home, and make sure the ground isn’t high enough anywhere to be in contact with the wood part of your home. What you absolutely need to avoid is anything that will keep the wood constant damp.


  3. maine_tyler | | #3

    If those are bottom plates, then they are buried in the stone? That's not good. Sounds like it could be tough to grade properly for drainage, unless the stone is currently pitched up steeply to the structure.

    Does this house have a basement?

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