Preferred Kerdi Shower Wall Material

[bcs001]

It’s very educational to see the back and forth from the pros in these threads. Ive decided to use drywall but wanted to ask if there was any reason to choose the mold resistant material. For as much as I’ll need the cost is negligible but thought I’d ask.

Bruce.

[cx]

You'll first hafta school some of us as to what mold resistant drywall might be. I'm familiar with alleged moisture resistant or MR board, usually green or purple or maybe some other color these days, but not mold resistant. But, then, I tend to be pretty out of touch these days.

But whatever it is, you don't need some. Should be no more likely to have mold growing behind the wall covered in Kerdi than in your living room wall covered in wallpaper.

My opinion; worth price charged.

CX

[bcs001]

I’m moving on to ordering the Kerdi components and from the past threads here I see there is an issue with lack of slope on the bench and curb. I think the curb will be easy to fix with a table saw by cutting a small angle on the bottom surface before installation.

The bench seems to be a more difficult problem. If I use their pre-fabricated bench, can the slope be done adequately by just applying the thinset thicker in the back when setting the tile? Or can the bench surface get a mud bed pre-slope built up before tiling?

Bruce.

[ss3964spd]

You don't want to use thicker mortar to achieve slope, Bruce, because water will get through the tile, the grout, and the mortar then just sit on top of the bench with no where to go.

You want to bench top pitched to drain before any water proofing method is employed.

[bcs001]

Has anyone come up with an acceptable way to slope these Schluter prefab’ed benches? Maybe the bottom and rear edges of the vertical supports can be modified to add a small angle cut? I’ve seen the recommendations to use the Better-Bench which I could consider if the Kerdi bench slope is a real problem.

[jadnashua]

Has anyone tried a belt sander to do this? The heat might melt it rather than erode it, but it might still achieve the same end result. You don't need much to achieve 1/4" per foot.

It isn't an approved method, but you wouldn't need much thinset to achieve this, either. A big flat edge, screed it with the desired slope, let it cure a bit, then apply the membrane over it.

If you build it out of Kerdiboard, you could easily engineer in any desired slope, but you might need a compound miter for some situations, but you could probably achieve it with just thinset while assembling the panels. The same with setting the curb.