Wet behind caulk [Archive] - Ceramic Tile Advice Forums - John Bridge Ceramic Tile


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07-09-2019, 06:17 AM
I last showered at 7 AM

At 7 PM I removed the caulk at the bottom of my shower - where the wall tiles meet the floor tiles. The back of the caulk was wet and the seam where the wall tiles meet the floor tiles was moist.

It is now 24 hours since my last shower and 12 hours since I removed the caulk and the seam where the wall tiles meet the floor tiles is still moist. Not moist enough to penetrate a piece of toilet tissue but not dry either.

Is this normal?

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07-09-2019, 06:29 AM
Attached is a photo (it is sideways)

John Bridge
07-09-2019, 08:24 AM
Hi Yankuba , :)

Yes, that is usually the case. Once water gets into that joint it can take several days (or weeks) to completely dry out. The leaky caulking inhibits evaporation while continually allowing more water to enter. Leave it alone another few days and then re-caulk with 100% silicone. :)

07-09-2019, 10:07 AM
Thank you John. If the caulk was letting water into that joint is that a problem? Should I be worried that the water got behind the tile and up the wall? The tiles are secure to the wall and I don’t see or smell any mold.


02-07-2020, 09:18 AM
So in July 2019 I had a grout company regrout my shower and caulk the shower pan.

Currently, the caulk on two sides of the shower pan is cracked. The job description said silicon caulk for the shower pan but I just learned they used Custom sanded ceramic tile caulk which is not 100% silicon. I called the caulk company and they said not to use that product for shower pans.

So I scraped out all the old caulk on all four sides of the shower pan and want to install the GE 100% waterproof silicon but the joint where the wall meets the floor is still damp. When I scrape the joint with a utility knife the stuff I pull out on the blade is moist. It has been a week since the last shower.

I don’t know anything how my shower was built - the previous owner hired people to build it. But is it normal for the shower pan joint to be moist for so long? All my tiles are secure and I don’t have mold or bad smells. The shower is 10+ years old.


Fast eddie part deux
02-07-2020, 09:43 AM
Might help to put a fan on the floor to force air circulation into the joint.

02-07-2020, 07:40 PM
If you dont know how the shower was constructed, I'd recommend against poking a utility knife too far into that joint. There may be a waterproofing membrane directly underneath the tiles.

02-11-2020, 09:08 AM
Thank you Dan and Eddie

The shower pan is now caulked with 100% silicon.

I know there is a debate as to whether the shower pan should be grout or caulk and the guidelines say caulk. Grout will usually crack where the floor tiles meet the wall

I just worry that when moisture gets behind the walls it won't be able to escape via evaporation through the shower pan joint. That the caulk will hold in water.

I believe that if the shower is constructed properly any water behind the caulk will drain through the cement bed and weepholes. But I can't help worrying about water trapped behind the walls.

02-11-2020, 09:16 AM
As long as the caulk doesn't completely fill the void (from the face of the tile all the way back to the wall) water should still be able to reach the pan.

02-11-2020, 09:26 AM
Thank you Dan but I don’t understand. The grout guy filled in the empty space/joint between the floor tiles and the wall tiles with silicon. Is that okay? I am at work - I don’t have a photo.


02-11-2020, 09:30 AM
Have a look at this thread, Yankuba, it does a better job of describing what I mean.


02-11-2020, 09:54 AM
Thank you - that was helpful.

In my case, in some locations I believe the floor and wall tiles exactly meet each other and there is no seam/gap or way to slide a piece of paper between.

In other places it looks like there is a vertical gap between the floor tiles and wall tiles - not a horizontal gap like the hand drawn picture in the link you sent. The silicon in my shower did not get pushed sideways through the wall cavity. It only got pushed down.

Am I okay?


02-11-2020, 10:11 AM
From the photos, Yankuba, to my eyes it appears the floor tiles do not extend under the wall tiles at all. Looks like they end well short and the gap between the two was filled with grout originally.

I think it's unlikely the entire void was filled with caulk.

02-11-2020, 10:23 AM
Thank you. I agree that in some places it looks like the floor tiles do not run under the wall tiles.

So am I okay with the silicon installation? Should I be worried about anything?


02-11-2020, 10:35 AM
I think it's highly unlikely he was able, let alone willing, to smoosh enough caulk into those gaps to completely fill the voids behind them along the entire lengths.

If the entire void was not filled then water should be able to drain down behind the new silicone and into the pan. I'm sure you appreciate that no one can say if it will be fine without the benefit of knowing how it was first built.

I think you'll just have to wait and see.

02-11-2020, 10:42 AM
Thank you very much for your help!

02-11-2020, 10:44 AM
Sure thing, best of luck with it!

02-11-2020, 11:43 AM
even if the floor tiles press against the wall/or will tile, it will NOT be a water tight seam. water will find it's way down.