Shower Pan Thickness

[RetroActv]

Hi all - first time poster here! What a great site for information.

I'm working on finishing my basement in Minnesota and getting close to needing a plan for the shower area. I've decided to go with a custom pan and use the Kerdi system. I've purchased the book here and have started reading through it.

I put in the p-trap for my shower drain a while back closed up the area. I realize now I probably made a mistake in leaving the shower drain too high, though it doesn't sound impossible to resolve.

So here's what I'm thinking - If I cut the drain pipe flush, I think my shower pan will need to be about 1.5" in the middle based on the Kerdi drain height? That's a guess; maybe someone knows for sure.

I know that's maybe a bit thicker than normal, but I'm also planning on using dricore r+ in my basement, bathroom included. That would raise the subfloor 1", so even with the additional height of the shower pan, it would be mitigated a bit since the bathroom floor would be higher.

Does this sound like an OK approach, or do I need to consider something different? By the way, shower dimensions will be about 56x34.

Thanks for the help and any other tips!

Nick

[jadnashua]

I think your numbers are off...unless you can recess the bowl/funnel of the drain below your slab, you'll need nearly 3" underneath the rim of the drain. https://sccpublic.s3-external-1.amaz...ta%20Sheet.pdf
Over a slab, you would do a bonded mudbed and that can taper to near zero underneath the drain, but the riser itself ends at the bottom of the taper.

[RetroActv]

Thanks! I think I can take off about 2" from the drain beneath the slab, so that would put the drain up about 1", which it looks like exceeds the minimum thickness at the drain? I'll take a look and make sure that provides enough material to properly secure the drain to the waste pipe.

[RetroActv]

Based on this picture I found on the site, if I wanted my drain to be 1 1/4" above the slab, the drain would need to be cut 1 1/2" below the slab, I think?

[Gregk2]

Nick,
Are those sole plates pressure treated? If not, did you isolate them from concrete with something like felt paper so they don't wick moisture from the concrete?

Are you planning to put a finish flooring over the dricore ?

[RetroActv]

Hi Greg,

The sole plates are treated. I had originally used wood for a shower curb, but it was too close to the toilet flange (about 16"), and I used PT wood and later learned that could create some problems as it dries. So I think I'll likely use bricks now.

I plan to use vinyl planks over the dricore.

[Tiger Mountain Tile Inc]

Bumping this because the question in #4 hasn't been answered yet