Question about molded floor joists

[Dillon Wyatt]

Hey all, I am not sure if this is the right place to ask this type of question or not. But here it goes.

We are in the process of buying a house. There are some pretty bad mold and moisture issues in the crawlspace of this home. The seller has agreed to remediate the mold, install a vapor barrier, and install a new sump pump.

We had a home inspection done (which raised awareness of these issues) and then a foundation/crawlspace/basement expert who quoted us a lot of things including some structural woodwork under an addition. I was under the house with the guy from the company, each of 10 floor joists had a bunch of mold on them and he was able to push his screwdriver through the width of the joist as well as up to the hilt of the screwdriver from the edge of the joist closest to the ground up towards the subfloor.

Our seller's mold company did not think these joists needed to be replaced.

How do you know when a floor joist needs to be replaced and is beyond being structural safe? To me, it seems like a screwdriver going all the way through a joist means they are pretty much gone.

[Jerry Peck]

I am reordering your comments to provide your answer.


I was under the house with the guy from the company, each of 10 floor joists had a bunch of mold on them and he was able to push his screwdriver through the width of the joist as well as up to the hilt of the screwdriver from the edge of the joist closest to the ground up towards the subfloor

Our seller's mold company did not think these joists needed to be replaced.

How do you know when a floor joist needs to be replaced and is beyond being structural safe? To me, it seems like a screwdriver going all the way through a joist means they are pretty much gone.

When you can ...


... push his screwdriver through the width of the joist as well as up to the hilt of the screwdriver from the edge of the joist closest to the ground up towards the subfloor.

Tell the seller's mold company to demonstrate doing that to good, solid, wood joists.

I doubt they can make more than a small dent into the surface of good, solid, wood when trying to push in a screwdriver ... if he can push a screw driver into and through good, solid, wood joists ... he is a candidate for 'strongest man in the world'.

[Jim Robinson]

I would trust your instincts on this one and plan on replacing the joists, one way or the other.