Messages and Online Forum Q&A

Re: dry rot

From: info@builderswebsource.com
Category: Foundations and Basements
Remote Name: 63.198.181.43
Date: 20 Oct 2000
Time: 10:07 PM

Comments

Before you go to the expense of repairing your sills and joists, you need to address the fundamental problem of moisture build up in your crawlspace. Even with ventilation, it sounds like humidity is persistent -- probably due to inadequate drainage, sprinkler irrigation, and/or insufficient soil grading. Builders Websource offers several good tips on drainage, both in our Tech Notes section, as well as in our online e-book, "Building a Dream." We highly urge that you read these first.

Once you remedy this situation with proper engineering, you're ready for the next step. Depending on the extent of the damage, this repair job may require a company that specializes in foundation repair. One method is to carefully "disconnect" the house from the sill plates, and jack it up enough to install new pressure-treated mudsills. These must be anchored into the concrete foundation with the existing J bolts. If the bolts have rusted due to extended moisture, new bolts may have to be blasted or epoxied into the the concrete.

Then, depending on how many floor joists need replacing, they could be selectively replaced or joined in parallel to existing members. Using a good bead of construction adhesive along the top will help to adhere the subfloor and minimize squeaking. You may also have to replace the rim joists...at which time you could install foundation vents every 32" or so.

If you opt to jack up the house, you might also use this opportunity to excavate 4-5" of topsoil from within the crawlspace....and replace this with sand, a vapor barrier and 3"+ of concrete rat proofing. This will help keep your crawlspace dry and clean.

If your damage is less extensive and isolated only to a few members, you may be able to replace those memebers with minimal jacking -- just enough to creatively remove and insert new lumber where it's needed.

No matter what, this is a significant repair job. The foundation and structural component of your house is the most important part. If it's failing, sooner or later it will impact the overall structural integrity and safety. Also, with this level of humidity over the years, you may also have a nasty termite infestation requiring fumigation or other ground treatment.

Good luck!

Builders Websource

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