How to Avoid Black Mold in Your Shower

How to Ensure You Don’t Get Black Mold in Your Bathroom Shower

Hello everyone. Today I wanted to talk a little bit about waterproofing in showers. We have a shower that we are currently taking out and at the bottom we’ve found that there’s a lot of mold growing and in the step that went up and over to get out of the shower.

Waterproof Your Shower

When you install your shower you want to make sure you have the correct waterproofing, so this is some kind of a tar paper. This house is pretty old so tar paper is what they were using back in the day. This tar paper didn’t go all the way up and over the step, it’s about an inch lower, so what this needed to have had was to continue longer and go up and completely over the step and down the other side, and then have this step slanted into the shower to drain into the drainage.

Why You Need to Waterproof Your Shower

What this did was any water that landed on the step or on the horizontal portion, went in through the grout and down into all the wood that was stacked up, and that all turned to mold. This is all molded and falling apart, and this whole shower essentially failed. And it’s really a. I mean, you have to redo it and then there’s that cost, and there’s also the health and safety hazards of having mold in your home.

What Dansie Design Build is Doing for a Client with Mold in the Shower

What we’re going to do with this client shower, when we replace this, we’re going to put another tile surround in. We’re going to have a fiberglass base, and we’re going to cover that with Red Guard, it’s a waterproofing membrane, fluid applied, and then that will waterproof everything behind the tiles so that none of this will penetrate through.

Black Mold in the Bathroom Shower

What they did was tile and then their mortar, was thin set and had some lath, which is this metal, and then they had a little bit more mortar thin set, and that was essentially the whole entire wall, there was no drywall, there was no waterproofing other than a little bit of tar paper at the bottom. So all that water splashing around coming in the shower, coming through the tile, especially through the grout joints and then into the wall and then became really humid when the shower was use. 

As you see down here toward the bottom of the wall it starts becoming very black, that is a problem. So up here toward the top where there’s less water there was less humidity. This wasn’t waterproofed correctly and so we’re going to redo it here.

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