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thegogetter222 10-24-2011 11:26 AM

Concrete Slab home; void under bathtub
Hey guys, just bought my home this summer. Any idea why there's a void (visible through the tub access panel down to the dirt) under the bathtub while the rest of the house is concrete slab? I see at least 1 joist that is completely rotted. The bathroom is full tiling.. floor and walls with jacuzzi tub, very nice. I'd hate to rip it up... just wondering what your thoughts are.

Thank you!

nealtw 10-24-2011 01:37 PM

Not sure what joist you see. That hole the concrete is pretty standard, it allows room for the trap under the tub.

thegogetter222 10-24-2011 02:08 PM

yup... that would show my humble position of novice : ) The joist I see is the supporting joist that goes under the center of my bathroom all the way to the wall. In fact, the "void" fills with water in heavy rain... which is a whole other drainage issue I have to address in the spring.

Hmmm... thinking... I need to see if I can in fact see the concrete slab from within the hole. I'll need to use a mirror, but I should certainly see it not to far off, right?

nealtw 10-24-2011 03:01 PM

Maybe I just missunderstude, here if you have a slab house, you live on a concrete floor. If you have floor joists, you should have a crawl space? Anyway the water there is a problem.

thegogetter222 10-24-2011 07:43 PM

ok, I've posted 2 pics here on my picasa: w&feat=directlink

Pretty bad rot... not too sure what to do about it besides proper drainage on the outside of the house then eventually a bathroom remodel

nealtw 10-24-2011 09:42 PM

You need to sove the drainage thing and open the floors around the house and dry this out properly.

BridgeMan 10-25-2011 01:13 AM

Homes built on slabs do not have floor joists. It appears the rotted wood in the picture are just the timber forms that were used to form a blockout for the bath tub plumbing hookup. Not totally uncommon, but forms are usually removed prior to tub being set. That looks like an after-market whirlpool tub, too.

Once you get the outside drainage issues corrected, you might want to make an effort to dry out the rotted wood before it starts to smell, or grow nasty little critters that like to roam the halls at night. Eeek!

thegogetter222 10-25-2011 04:38 AM

awesome, thanks guys : )
I know I have a drainage issue that needs to be addressed sooner rather than later.

all the best

joecaption 10-25-2011 08:51 AM

I also live in a slab home that the slab was pored to low.
I had to add a french drain around the whole house. I also added a second line (4" sch. 20 PVC) and piped all my down spouts into this pipe and had to add a pit with a pump in it because there was no grade for run off.
While I had the footing and block exposted I sealed the foundation with foundation sealer.
Once this was done all my mold and water problums went away.
The total cost was only a few hundred dollars because I did all the work myself. The biggest cost was the new sump pump.

thegogetter222 10-25-2011 11:08 AM

interesting... thanks for the info. Do you have a dry well? where does your sump pump the water too? i was thinking about auguring a dry well for this process.

On a different note or post even:
I also do not have any grade to route with. All my gutters, 2 front driveway drains, and 2 internal garage drains, already run into an underground pipe that runs the perimeter of my house, but I CANNOT FIND WHERE THE WATER RUNS TOO! I have tested it with the hose, listening to my septic with the lid off and no water or noise. I literally have no idea where this water is going. Any thoughts on this issue? wowsa!

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