Rot Doctor


Subject: Rotting foundation sill plate
Date: Tue, 20 Jul 1999

I found a home that I would like to purchase and I had a home inspection done. There is a noticeable pitch to one area on one wall inside the house. The home inspector went down into the crawl space and found that the sill plate in that area has rotted away. There is a leak from a bathtub above it and rainwater (from lack of a gutter) drains down near that area.

My question is what does it entail to repair or replace that sill? What would it cost. The inspector spoke about a sister sill? or shims. He also spoke about jacking up the house but really seemed to shy away from what it would entail and referred me to getting a contractor in to look at it. Thanks in advance.

The question of what is involved in repair/replacement is hugely variable and consequently, so is the costs involved. One might decide to soak all the bad wood in CPES, shim up the sagging studs so that they don’t sag further, and call the job done. Or you could carefully jack up the sagging wall, remove and replace the badly rotted parts of the sill plate, treating all old and new wood with CPES and let the house back down on the new plate. If you decide to jack the wall back up, you might create a crack in the sheetrock/plaster on the interior wall. How much of the plate is rotted? Did the rot get up into the studs? Is there plumbing in the wall that might get cracked when the wall is jacked up? All of these factors could change the price of the repair and make accurate estimating difficult.

Treating and stabilizing the existing structure would probably be the cheapest, and have the least probability of additional expenses (cracked walls, etc.). Whether the inspectors would be happy, and whether you would be happy with a sagging wall is another matter.

As long as I didn’t have any great reason not to, I’d probably jack the house up and treat and repair the bad wood. A little more expensive, but I’d sleep better. Of course if you decide to follow our advice and something bad happens, we are in no way legally responsible. Sorry, have to keep the lawyers happy. This is why the inspector advised a contractor. They SHOULD be more aware of potential pitfalls, and (providing you choose one that is licensed and bonded) are legally responsible should anything bad happen.

Whatever course you decide on, I would treat the wood with CPES. If water comes in contact with CPES treated wood, it is very hard for the moisture to get into the wood. This in turn makes it very hard for the rot fungi and bacteria to start growing. Don’t forget to fix those leaks, too! :)

If you have any further questions, please let us know.