Water leak has swelled oak floor

Old 03-29-24, 02:59 PM
eddieo45's Avatar
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Water leak has swelled oak floor

I had a few problems in my house that I didn't realize were related until I ended up with what seems to be a worse problem than all of them. First, around Thanksgiving, I had an issue with a loose shower valve handle that I came HERE for advice about. @Norm201 told me the handle was just loose so I tightened it but continued to have issues; it would turn on but also off if I continued turning it to the left. Then, just before Christmas I had paint bubbling up on the wall of that same bathroom, posted that one HERE too; @tightcoat said it was possible there was a leak behind the wall and @manden suggested I tape plastic over the area to see if any moisture showed up; it did, but it took a long time, maybe a few weeks. During that time my wife complained that the door of another bathroom was not clearing the floor. I chalked that up to the house settling and trimmed about a half inch off the bottom of the door. The vinyl in that bathroom started to "bubble", as if it was expanding or something. Well, come February I went down the cellar for something unrelated and saw that there was indeed a leak. Just a steady drip but I could see that the subflooring was soaked. I got my plumber in right away; the valve inside the wall had come loose (I like to think that had to be his fault).
Here's a pic of where the oak floor butts up to a vinyl piece that used be the floor to a closet we removed:

It seems like that lightweight table kept it down in the middle but you can see the bowing on either side of the table leg. I searched the web for solutions to the floor damage and saw many suggestions to run a dehumidifier as long as it takes and it will eventually return to normal so that's what I've done: I put the dehumidifier and a fan on a table in the cellar aimed right at the leak site. I have it draining into a 5 gallon bucket, which it filled in a couple of days originally but now I'm getting about half a bucket per week. We've been getting a lot of rain and cellar floor gets (and stays) wet.

Do you think the dehumidifier will eventually dry out the subfloor? Should I add more fans?
Old 03-30-24, 06:29 AM
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If your basement floor is staying wet you've got a lot of problems. If you don't keep the water out of the house's perimeter you'll forever be fighting a battle with humidity and have the problems that comes with it like warped & swollen wood and mold & mildew.

Plank flooring is nailed down in strips. Once it's buckled badly the nails may have pulled so it might not settle back on it's own. Once you get it thoroughly dried you might try putting a scrap of wood on the floor and try hammering it down with a medium heavy hammer.
Old 04-06-24, 06:27 AM
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I am not clear what floor this is happening on. But if it's on the second or first floor and your house was built with Oriented Strand Board (OST) rather than plywood, that could very well be the problem. OST boards make up about 1/2 of the floors in houses built over the past several decades, because they cost about half as much as plywood. They are some 20-30% denser than plywood because they are pressed under high temperature and pressure. The problem with them is that they only perform well in dry conditions. When exposed to water, especially at cuts, they swell up heaving any flooring that sits on them!

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