It started as a simple leak behind the washer

[vinny11950]

So I took off some sheet rock to find the source and I found crap (mouse or squirrel), chewed up insulation, and sand with rocks in it (wft)!

And these pictures are after some cleaning.

Behind the wall is the bathtub in the basement bathroom.

Can't understand why they would put sand underneath the tub.

Also found some black mold. Personally I am not that worried about it, but should I be?

 

[Dune]

Sand likely a crude attempt to support tub. Mold isn't good, try some bleach.

 

[Ehouse]

Bedding the tub in morter for support is/was standard practice.

Ehouse

 

[Highbeam]

I've used spray foam beneath shower/tubs but your'e supposed to bed them in something permanently supportive like plaster. Sand is weird because unless it is confined it has nearly no compressive strength.

Did some sort of insect deposit this "sand" like ants or termites?

 

[semipro]

I'd be worried about the mold but you should be able to kill it if you keep it wet with a bleach solution for long enough.

You have a water problem but you said you were chasing down the leak. My advice, fix the leaks, kill the mold, replace any lumber that's not structurally sound, install an access panel for future access.

Having had two tubs that cracked on the bottom we know the importance of proper tub support. Perhaps what looks like sand is actually mortar; or sand mixed with portland cement then wetted to create a bed for the tub? Hey, at least they tried to support the tub right.. Many don't.

 

[Jack Straw]

It looks like a steel tub to me, so you might not need a lot of support.

 

[eclecticcottage]

I used vinegar on the mold we found here. You'll probably want to look for cracks and holes where the varments are getting in. We've been there and are still doing that-the Cottage was empty several years before we bought it so they got pretty used to coming and going as they pleased.

We had a tub water leak also. We created an access panel in our hallway where the plumbing is and you'd never guess it was there. It's a piece of plywood covered in beadboard that's screwed to the wall. The trim is brad nailed over where the screws are to hide them, so if we need to get in there we just pry off the trim and unscrew it.

I'd make double sure that is sand. If it is and wasn't cement that got exposed to a lot of water...it was probably someone's idea of "leveling compound" for the tub. Otherise, another thought might be that since it's a basement, they didn't clean up after themselves when making holes for plumbing in the concrete and that's just part of the floor that was removed to run your lines.

 

[vinny11950]

Sorry for not responding right away, guys. I was away at work.

Thanks for the replies, they have really helped me understand the problem better. It seems this bathroom is a hack job probably done by the same hack who screwed up the fire alarm wiring in the attic.

There is mold behind the wall because they tiled over regular sheet rock and it looks like the grout failed and leaked. In the moist basement environment, the mold thrives even though that shower is never used. The pipe leaked was not as bad as I thought, just a leaky valve that needs changing.

As for the sand, I am thinking along the lines of Eclectic Cottage, that the builders were lazy and dumped debris there - also found other trash in there.

I think I will just tear down all the bathroom walls, maybe the studs too, if they are bad.

 

[nate379]

Hard to tell but is that sill plate PT wood or a foam barrier between the wood and the slab? Maybe moisture wicking up from the slab?

 

[StihlHead]

Wet wood is not good. We have several species of ants here that will eat wood fungus. Good news is that they clean up the mess, bad news is that there is rot and fungus to attract the ants. Here they got into a small section of my roof eves that was wet from a leak and rotting, and they left a sand like residue behind. I replaced the rotted plywood this summer and the ants have not returned. Rodents (voles, rats, and mice) drag in all kinds of things here, including dirt, sand, walnut shells, etc. They nest in the insulation under my house, so I opened the crawlspace for my cat to hunt down there, and no more mice, rat or vole damage.

As Nate mentions, are those PT sill plates? Here PT is required by code for all wood in contact with concrete. Strong bleach works wonders on modly sheetrock. If the midlew is in the wood it is hard to get rid of the smell though. I found that a coat of clear poly works well to cover over/seal in the smell. I would run the taps to the tub and make sure that the plumbing has no leaks, and also check the drain. I had a similar problem in one bathroom here where the hot water valve seat was shot and leaking into the wall and under the tub when the shower was being used. I had tp replace about 3 square feet of partical board flooring on the adjacent room flooring that was rotted out as a result. It had been leaking for years...

 

[semipro]

Sorry for not responding right away, guys. I was away at work.

Thanks for the replies, they have really helped me understand the problem better. It seems this bathroom is a hack job probably done by the same hack who screwed up the fire alarm wiring in the attic.

There is mold behind the wall because they tiled over regular sheet rock and it looks like the grout failed and leaked. In the moist basement environment, the mold thrives even though that shower is never used. The pipe leaked was not as bad as I thought, just a leaky valve that needs changing.

As for the sand, I am thinking along the lines of Eclectic Cottage, that the builders were lazy and dumped debris there - also found other trash in there.

I think I will just tear down all the bathroom walls, maybe the studs too, if they are bad.

Vinny, I've seen this before. It really looks like you had water on the floor that wicked up through the framing and drywall to enable the mold growth. A typical moist basement environment or tile over standard drywall did not cause the mold shown in your photo. Damage like this occurs when the area stays constantly wet for a while. I suspect your tub leak was worse than you think and probably the cause of the damage. Even a very small but constant drip from a leaking valve could cause this.

Agreed that a barrier or PT sills are needed but simple contact between sills and concrete likely didn't cause this problem.

 

[vinny11950]

You guys are all correct. The sill is not pressure treated so it absorbs moisture from every where. I think it will have to go too. I want to tear down the basement in sections. The bathroom might be first after this. There is no sense in keeping the wall studs if the sill is moldy and rotting. I am wondering if the other walls suffer the same by wicking moisture from the slab, as Nate suggests.

It is crazy how leaks can go on for long times without being detected and causing so much damage.

 

[eclecticcottage]

Lol...or, you could have a leak that IS detected but then just covered back up instead of being fixed, like this:

that is cement/thinset that was used to fill a hole in our wood floor caused by the leaking tub I mentioned before. It was then covered up and they laid carpet. A squishy spot which was a slightly darker color was our notification that there was a problem.

 

[vinny11950]

Lol...or, you could have a leak that IS detected but then just covered back up instead of being fixed, like this:

that is cement/thinset that was used to fill a hole in our wood floor caused by the leaking tub I mentioned before. It was then covered up and they laid carpet. A squishy spot which was a slightly darker color was our notification that there was a problem.

wow, eclectic, that's nasty.

homes are strange things, because, generally, their value goes up, even though they decay like everything else, but that decay can easily be covered up by the seller.

my home was built in 1972. i bought it as a short sale in 2009. even though i got a good price compared to the other homes in the neighborhood, I still have had to do a ton of work, and more is in store.

I often think how much trouble previous owners/builders would have saved me if they had just spent a tiny more to build it right.

if i had to do it again, i would have looked for a newer home, as it appears the town really stepped up their building codes in the1980s.

still, i shouldn't complain, as others have much older homes, but even those older homes have designs and materials that offer advantages over today's buildings.

 

[eclecticcottage]

It was bad, but the living room was worse. That wasn't built on a slab (it's an addition) and the sill had rotted away to nothing, literally. A friend that's a contractor that was helping us with some things in that room didn't believe us at first when we told him there used to be a sill plate until we showed him was was left sitting in the holes in the cinder block (foundation). We tore out the whole floor, joists and all in there. The floor had basically dropped 2" or so because of the rot.

We weren't really surprised and figured we'd be into just about everything in the place at some point when we bought it. It was built as a summer cottage, added on to and lived in, flipped at one point, was a rental, and finally was vacant when we bought it. I really don't mind though, this way we know it was all done right.

A properly maintained home won't decay. The problem is, many people don't want to do the work to maintain them. The Cottage suffered from a lot of what I call deferred maintainance-even relatively simple things like painting the trim around the windows hadn't been done in a VERY long time.

It's funny because I don't consider the Cottage old. It was built in the 1950's. It has to be pre1900's to be old to me...

 

[woodgeek]

eclectic....I have perused the blog and am in awe.