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SwellWill 05-08-2013 11:27 AM

Water Under Bathroom Ceramic Tile
Last night, I discovered a leak in my downstairs bathroom. The leak was coming from the toilet water supply valve, I have currently closed it to temporarily prevent additional leaking. I went into the crawlspace under the bathroom and confirmed that it was leaking through.

It looks like water has gotten underneath the tile, and I was able to get moisture to seep at the tile joints when I step on them. The water also got to my carpet too just outside the bathroom door too. I have pulled the carpet up and exposed the underpadding and wood base to dry more efficiently. I turned on the bathroom exhaust fan last night to try to get some airflow in there.

I checked the crawlspace this morning (~7 hours after leak was stopped), and verified the leak has stopped. Several damp spots have dried up under there, but there are still wet spots (most likely where the most severe leak-throughs and "wick" spots. I pull a minor ceramic tile that borders a floor air vent, and saw that the wood is damp/wet on top as well. I stepped on the tiles again to check for seeping moisture at the joints, its still there but slightly less severe then last night.

I closed the bathroom door and left the exhuast fan on this morning and will check on it again this afternoon. Will tile removal removal be necessary to address the moisture at this rate with the current measures that I have taken? I live in a relatively low humidity area (Colorado).

Thank you in advance for your input.

JetSwet 05-08-2013 12:50 PM

Yikes. ... so I may ask you have tile over plywood?... and a air vent in bathroom floor or base board heater? Was your toilet did the water get below the floor?

SwellWill 05-08-2013 01:12 PM

I am renting this house and will try to answer to best of my ability.
Yes, I believe it is tile over plywood.
It is an air vent on the floor itself.
I didn't notice any caulk around the base of the toilet, should there be? I hope that I stopped the leak which I believe was coming from the toilet water supply valve.
I am not completely sure how the water got below the floor. The leak seemed minimal and may have been active for some time. The water could have seeped through the grout, wall edges, at the base of the toilet, etc... This is a very small bathroom, just a toilet and sink underneath the stairs.
My first concern is mold prevention and mitigation.


JetSwet 05-08-2013 01:22 PM

Best method for now is to air it out the best you can with fans windows opened ect. If the plywood got wet enough then it would warp and cause your tiles to pop.
I would check all grout lines and make sure there are no openings on the floor. Open the floor vent and point fan at it.

If the toilet wasn't silicone or chalked that's another area to inspect as well.

Seattle2k 05-08-2013 05:08 PM

Since you rent this house, have the landlord worry about fixing it. Their homeowner's insurance will cover the tearout, drying, and repair work.

MTN REMODEL LLC 05-08-2013 06:03 PM

Dry it out.... but if the grouut lines were squishing water, it's likely the tile/subfloor bond was broken, and the tile should be reset and regrouted.

Colorado's dry, but we still get mold. Put fans on it. If any appears on the sheetrock etc, whack it with some 25% clorox 75% water mix.

(There are other more protective products, but I doubt you'll need them)


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