Mold around tub caulk. Is this bad?

[joshhudm]

Here are some picture of what i can only think is mold coming around the caulk connecting the tub and the wall. This a crappy reno before we bought the house and im worried mold is growing behind the wall and under the tub. It doesn not really scrub off, at least easily at all. Any tips as why this is happening i would appreciate it.

[HayZee518]

mold is feeding upon the paper backing of the drywall and maybe the tile cement. got to remove the tile and the sheetrock underneath. moisture has worked its way under the tile and will keep on increasing unless the source is corrected

[joshhudm]

had a feeling.. so basically have to tear apart the bathroom and do it correctly, right?

[joshhudm]

could this turn into a MAJOR problem like a mold infestation? aka is it something that needs to be done?

[pushkins]

BEFORE you go tearing anything apart, remove the caulk, dry the area and see if you see any "seepage" in the newly dried area. Many, many times it's just the caulk, cheap caulk will mold over like your pictures very quickly and (esp. cheap caulk) will grow mold very well.
There are cleaning products that claim to clean mold from caulk but they infact degrade the caulk making it much more mold friendly.

So clean out the area, by removing the caulk, dry the area and then inspect it to see if any moisture appears. Where your pictures show mold there would be no drywall, there will be a lip on the tub.

[joshhudm]

always can count on you. This caulk is really hard. i had a plastic caulk removing tool and it did nothing. Im assuming they make a metal type would be that your suggestion for removing the caulk? Also how long should i wait with the caulk remove to check for moisture? Thanks again!

[pushkins]

If the caulk is uber hard it's more likely an adhesive caulk (which by the way will mold very well in the right conditions). You may have to resort to a sharp box knife BUT be very carful not to either slice yourself or the tub. Sometimes if you can get a piece started the rest will pull out with it. If you have a multi tool this will make life much easier as well.

Once the caulk is out dry it with a clean cloth, wait a couple of minutes and look to see if you see any moisture appear. If the moisture keeps appearing (after a couple of clean and dries) then it's probably a good indication of moisture trapped in drywall, tile glue etc...

Re caulk with a 100% silicon caulk one that mentions Biocide (it's a chemical that inhibits mold and mildew growth (GE make one for an example).
Your picture shows corner mold, make sure the grout is not cracked running up that corner if it is seal that area as well.

Don't use heavy chemical cleaners near silicon, the cleaners degrade the silicon allowing mold spores to attach and grow. A common mistake people make is they see mold, attack it with the strongest mold cleaner sold on the shelf, sure it removes the mold from the surface but in the process etches the silicone (made worse if you used a scouring pad at the same time...lol), this just gives the mold a bigger and better place to grab hold, making it harder and harder to remove each time.

[joshhudm]

So I took the caulk out and there still are dark spots under the faucet. Should I bleach those before I recaulk or its that just a bad sign

[pushkins]

Mold won't grip onto the tub finish and seldom to the tile (it will to grout ...porous), clean the area well with bleach, you might have to use a flat blade scraper to get any residual caulk off the tile or tub. You should be able to remove all the mold.
Clean and dry the area well, then reapply the silicon.

You should also be able to see the tub lip going up behind the tile ?
You don't see any drywall do you ?

[joshhudm]

Yeah no drywall. Actually seems like it is grout so honestly couldn't tell you what is behind that so no seeping either. Im about to recaulk now. Thanks again btw. You have helped me on everything I have posted on here.

[pushkins]

Always welcome