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Best of Three Methods for Repairing Foundation

1910duplex | Posted in General Questions on

My mother had a crawl space expert in Virginia come out to look at her 1987 home, and they said she had foundation issues. (A previous contractor had said her kitchen floor was uneven, and there are some minor cracks in her one-story home interior walls).

They offered good, better best options of $12,000 to $28,000, and she is thinking of the middle option.

I realize this may not be enough information to be useful, but in case anyone had insights, I wanted to try.

The good option is

permits and engineering, and an intellijack of 1 to 3 inches

Middle option is intellijack plus CrawlSeal 2omil liner (replacing 17-year-old liner) and a remote hydrometer.

Best option is replacing insulation and liner and remote hydrometer and dehumidifier and one other thing I’m forgetting related to monitoring humidity, I think. But the house is probably only worth $200,000ish, and my Mom may well sell in next five to seven years as she is 78.

If memory serves, the middle option was $16,000? Worth it?

She has not had any particular humidity problems in home, which is heated/cooled by heat pump. She lives in Richmond, Va, 4a

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  1. 1869farmhouse | | #1

    Are there humidity issues in the crawl space currently? I’d definitely put a 5 dollar hygrometer to verify. If it’s not terrible, the existing vapor barrier is probably doing its job - and the structural issues seem to be the more important piece.

  2. 1910duplex | | #2

    Thanks for the reply! I asked her to get a hygrometer and check.

  3. Expert Member
    Peter Engle | | #3

    The sagging and cracking may be due to rot/dampness. Damp wood is not as strong as dry wood, and if it rots it obviously loses strength. So if dampness is an issue, addressing the dampness is the first job.

    After drying out the crawl (or along with drying it out), jacking things back into place and shoring them up is generally a good idea, though bringing everything back to flat can be a challenge. I've always said thata you can get about half the sag out with jacking without causing too much collateral damage. More jacking than that and you have to plan to start removing and replacing interior finishes, trim, etc.

    But sagging can also be related to foundation settlement that has nothing to do with moisture. I've seen full waterproofing and encapsulation jobs done on houses that had defective foundations with no moisture issues, and vice versa. It is important to first identify the problems and their root causes, then make decisions about correcting them.

  4. 1910duplex | | #4

    Update -- Mom said there was mold on some of the insulation in there, and the liner is ripped, so it does sound like moisture is an issue. Perhaps that means she ought to do the full option with replaced insulation, dehumidifier etc., but I just hesitate with it costing more than 10% of her total home value, especially since she's likely not going to stay even 10 more years.

  5. Jon_R | | #5

    Personally, I'd probably DIY tape up any liner rips, install a dehumidifier and hygrometer and install a few jacks. Maybe < $1000 and 1 day of work.

  6. 1910duplex | | #6

    Well, I'm not handy enough to do the jacking, but I think we could install a dehumidifier the next time we go down there?

    1. Expert Member
      BILL WICHERS | | #7

      Dehumidifer installation is mostly installing a relatively small electrical feed and a drain line. If you need the water to "drain up", you can get small condensate pumps that are like self-contained mini sump pumps for this specific purpose.

      You will want to use the correct tape to tape up any tears in that poly liner. Usually that means a WIDE (3 to 4", wider is usually better) that is intended to stick to polyethylene. You can get this tape from places like Americover, among others. Don't try to use cloth duct tape here, it won't last long.


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