Hi, first post here.

So I bought a house where the master bath was remodeled. The shower is all tile, and there is a seat type of structure, so lots of areas where different planes meet. They used grout instead of caulk where those planes meet and the grout it cracked.

There has gotten to be some mold behind there. I found this out because of this smell that would happen after a shower. It took so much trial and error to find out what was causing the smell.

I have filled in the cracked grout with waterproof silicone caulk, and that is how I noticed the exact cause of the problem. After I ran water, there was no smell. So water would be getting into the cracks and then causing the smell. I don't know the science behind mold, so maybe the mold is dormant until the water hits it?

Anyways the silicon didn't stick in all places because I could not completely dry out some spots of the cracked grout. Anyways, this was just temporary to find out the exact problem.

I have now removed most of the grout. I'm now looking for suggestions on moving forward in the cheapest/easiest way possible.

Questions:

1. Can I eliminate the mold without removing the tile?
2. If I seal it up so that it is waterproof and water is no longer seeping through these cracks, will I be safe from the mold?
3. What do you suggest the best way to remove the mold?
4. Any suggestions for best caulk for this scenario?

TIA

 

What color are your tiles and grout? If white, you can use bleach and water solution. If colored, you would look to a cleaner for mold and mildew that is not staining.

Surfaces must be 100% dry before moving forward with caulking. An air compressor can blow the moisture out, a hair dryer can dry the area out.

Tile stores sell a color matching caulk that your can apply to blend and make it look like grout.

Edit - Welcome to the Forums!

 

Personally, I'm not super concerned with appearance. The remodel was done probably 10 years ago and the grout it discolored anyways.

I'm mostly concerned with:

1) Stopping water from getting through the grout
2) Removing the mold, and stopping the mold from getting into the air

So I want to know, do you think it is likely that I can remove all of the mold without removing tile? If so, how should I go about doing that? For example, should I get a spray bottle of bleach and continuously spray into the areas that I have removed the grout?

 

If the grout is not white, you risk color change using bleach. Shop the cleaning isle at the box stores they have many products designed specifically for mold. You just need to dry it out sufficiently before caulking. Once sealed, and without moisture, the mold will cease to grow.

 

I have not used the shower for approximately one year now, so I would think that it is completely dry (however I did not blow it out or dry with a hair dryer prior to stopping usage of the shower.)

Do you think it would be best to seal it up now without dealing with the mold (since using a cleaner on the mold would cause it to get wet again and I would have to dry it out)?

or, do you think I definitely need to attack the mold and get rid of it best I can before sealing up the removed grout?

 

If you can not see mold and the shower has been idle for a year, the mold is no longer active. Seal it with color matching grout and after a day or two go back to enjoying your shower.

 

Thank you for your input. I appreciate it.

 

There is no good way to know if there's mold left. However....... if it grew mold, that would tell you there's a food source for the mold to grow in the first place. This would indicate they used wallboard and/or mastic under the tiles, that is bad news for showers. Mortar and concrete covered with ceramic tiles will not sustain mold.

You asked:

Questions:

1. Can I eliminate the mold without removing the tile?
2. If I seal it up so that it is waterproof and water is no longer seeping through these cracks, will I be safe from the mold?

1. Probably not. I think encapsulating is the best you can do.
2. You can NOT seal it up so it'll be waterproof, can't be done.


Jaz

 

So what is waterproof caulking then?

Are you saying that the caulking is not waterproof? Or are you saying that water will get through the grout in the rest of the shower?