Tyke's_Place
New Member
Hello,
I'm hoping to get some advice on my basement shower project. Lots of reading and many questions are rolling around in my skull. But I'll start at the floor, which is a bit unique. Over the slab I have 2" of high-density polystyrene insulation, and then standard subfloor. The walls and finish floors are on top of the subfloor.
My goal is to remove the foam and subfloor where the pan will go. That's 2-3/4" thick. The pan would go on the slab. Then after the build up of the pan and tile, the shower floor by the curb will be a bit lower than the finished bathroom floor. Here's my diagram of the whole plan.
First step would be to cut the subfloor to remove material for the pan. I'd leave 14" of foam/subfloor as a base for a bench. I'd frame the bench, covering it with hardibacker to drain from the wall down to the pan. The pan membrane would come up behind the hardi at the foot of the bench, same as it will at the walls. Finally I'll install a 2" mortar bed for the bench seat. Any issues with that plan?
For the floor, I have a knockout in the slab. I plan to dig out the gravel to make room for the trap. Then install the trap so the drain is centered in the shower floor. Here's what I have now.
From my reading I think the best practice for the hole is this. After I set the plumbing and drain base, backfill the hole with packed sand or gravel to the bottom of the slab, then fill with 4" of concrete to match the finished slab.
I'm wondering about the height of the drain. I've already ordered the Kohler drain below. I think the thin flange below the weep holes should be at the level of the pre-pitch. Meaning if pre-pitch is 3/4" thick at the drain, then that thin flange on the drain should be 3/4" above the slab. Then the Oatey membrane lays over that and is clamped by the weep flange. Is that correct?
If so, then I really need to plan the pre-pitch correctly. I've also ordered the Kirb-Perfect Pre-Pitch and Quick-Pitch kits. Their site shows both of those kits being used for a shower pan. Both kits have 1/4" per foot slopes. So do I end up with 1/2" per foot for the finished pan?
Their directions show the pre-pitch bed going to almost nothing at the drain. But, that's with a slab and drain that are already done. I've read here and other places that 3/4" to 1" is preferred. Since I can set the drain at whatever height I want, then I can do the preferred thicker pre-pitch. Correct? Or maybe I can set the mortar bed to be thick enough to pretty much match the finished bathroom floor. That leads to my next question about the pan.
If use the Kirb-Perfect kits, each with its 1/4" per foot slope, then that's a total 1/2" per foot rise. That means I'll slope up 1" to the left of the drain, and about 1-1/2" to the right of the drain. So the perimeter of the finished pan will be out of level by 1/2" over the 5' width. Is that correct? Do I just adjust for that at the bottom of the wall tiles?
Thanks to anyone that takes the time to read all of this and provide advice. I really appreciate it.
I'm hoping to get some advice on my basement shower project. Lots of reading and many questions are rolling around in my skull. But I'll start at the floor, which is a bit unique. Over the slab I have 2" of high-density polystyrene insulation, and then standard subfloor. The walls and finish floors are on top of the subfloor.
My goal is to remove the foam and subfloor where the pan will go. That's 2-3/4" thick. The pan would go on the slab. Then after the build up of the pan and tile, the shower floor by the curb will be a bit lower than the finished bathroom floor. Here's my diagram of the whole plan.
First step would be to cut the subfloor to remove material for the pan. I'd leave 14" of foam/subfloor as a base for a bench. I'd frame the bench, covering it with hardibacker to drain from the wall down to the pan. The pan membrane would come up behind the hardi at the foot of the bench, same as it will at the walls. Finally I'll install a 2" mortar bed for the bench seat. Any issues with that plan?
For the floor, I have a knockout in the slab. I plan to dig out the gravel to make room for the trap. Then install the trap so the drain is centered in the shower floor. Here's what I have now.
From my reading I think the best practice for the hole is this. After I set the plumbing and drain base, backfill the hole with packed sand or gravel to the bottom of the slab, then fill with 4" of concrete to match the finished slab.
I'm wondering about the height of the drain. I've already ordered the Kohler drain below. I think the thin flange below the weep holes should be at the level of the pre-pitch. Meaning if pre-pitch is 3/4" thick at the drain, then that thin flange on the drain should be 3/4" above the slab. Then the Oatey membrane lays over that and is clamped by the weep flange. Is that correct?
If so, then I really need to plan the pre-pitch correctly. I've also ordered the Kirb-Perfect Pre-Pitch and Quick-Pitch kits. Their site shows both of those kits being used for a shower pan. Both kits have 1/4" per foot slopes. So do I end up with 1/2" per foot for the finished pan?
Their directions show the pre-pitch bed going to almost nothing at the drain. But, that's with a slab and drain that are already done. I've read here and other places that 3/4" to 1" is preferred. Since I can set the drain at whatever height I want, then I can do the preferred thicker pre-pitch. Correct? Or maybe I can set the mortar bed to be thick enough to pretty much match the finished bathroom floor. That leads to my next question about the pan.
If use the Kirb-Perfect kits, each with its 1/4" per foot slope, then that's a total 1/2" per foot rise. That means I'll slope up 1" to the left of the drain, and about 1-1/2" to the right of the drain. So the perimeter of the finished pan will be out of level by 1/2" over the 5' width. Is that correct? Do I just adjust for that at the bottom of the wall tiles?
Thanks to anyone that takes the time to read all of this and provide advice. I really appreciate it.
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