Author Topic: Poured shower pan (AKA "Relatively Sweet Shower") help  (Read 11098 times)

FIence!

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Poured shower pan (AKA "Relatively Sweet Shower") help
« on: September 15, 2014, 02:09:38 PM »
We are going to be tackling a poured shower pan as illustrated by MMM in the "How to make a relatively sweet shower - cheap" post. My question is about the roofing paper MMM uses at the base of the shower to keep moisture from wicking into the subfloor. Since, unlike MMM, we don't happen to have spare roofing paper, we would like to avoid the added expense of purchasing some and are looking for alternatives.

Our thinking is that something as simple as laying down contact paper on the wood might work. Or even stapling parchment paper or wax paper? Another thought we had was Redgarding the subfloor where the shower will be, but that seems like overkill if it's just moisture wiking we're trying to avoid. Maybe it's even ok to skip that step? I'd love to hear from people who have made the poured shower or contractors who might know what's best.

El Marinero

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #1 on: September 15, 2014, 02:15:39 PM »
Nooooooooo!

Contact Paper? Wax Paper? Parchment Paper? 

You are trying to save a few bucks now that could cost $hundreds later when the new shower has to be torn out to replace wood that rotted due to moisture.

You can buy shower pan membrane by the foot at lowe's or home depot.   There are other alternatives.  All are cheap compared to the cost of failed waterproofing in a shower pan.

Good luck with the project!

FIence!

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #2 on: September 15, 2014, 03:40:35 PM »
I'm not talking about using any of these things as long-term waterproofing for the shower. The showerpan itself would be waterproofed... the cement, once dry, will be covered with the trowel-on waterproofing membrane. This under layer is just to keep the subfloor from drawing moisture away out of the (relatively dry) concrete mix while it is drying, which should only be a few day process. It is just a barrier between plywood and drying mason's mix.


dragoncar

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #3 on: September 15, 2014, 04:47:20 PM »
I'm not talking about using any of these things as long-term waterproofing for the shower. The showerpan itself would be waterproofed... the cement, once dry, will be covered with the trowel-on waterproofing membrane. This under layer is just to keep the subfloor from drawing moisture away out of the (relatively dry) concrete mix while it is drying, which should only be a few day process. It is just a barrier between plywood and drying mason's mix.

Why just a cut open garbage bag then?
      ^not

ArtieStrongestInTheWorld

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #4 on: September 15, 2014, 05:24:22 PM »
We are going to be tackling a poured shower pan as illustrated by MMM in the "How to make a relatively sweet shower - cheap" post. My question is about the roofing paper MMM uses at the base of the shower to keep moisture from wicking into the subfloor. Since, unlike MMM, we don't happen to have spare roofing paper, we would like to avoid the added expense of purchasing some and are looking for alternatives.

Our thinking is that something as simple as laying down contact paper on the wood might work. Or even stapling parchment paper or wax paper? Another thought we had was Redgarding the subfloor where the shower will be, but that seems like overkill if it's just moisture wiking we're trying to avoid. Maybe it's even ok to skip that step? I'd love to hear from people who have made the poured shower or contractors who might know what's best.

I actually just poured a shower pan at my house two weeks ago, so this is fresh for me.  It's okay to pour your mortar bed right on a plywood subfloor (not okay if you have OSB), but better if you can use a slip sheet.  Tar paper is okay (like MMM), or you can use 6 mil plastic sheeting.  Neither one is very expensive, and for something like a mortar bed (where mistakes are not easily undone), I'd rather do it right the first time if I were you.

Not sure if you bought the Redgard yet, but that stuff is super expensive, and would definitely be overkill for a slip sheet.

Good luck, post some pictures when you're done!

FIence!

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #5 on: September 15, 2014, 05:49:04 PM »
Yeah, don't know why I didn't think of the plastic sheeting, guess I was thinking of things that would be flat to the floor or even stick to the floor. That's a good idea!

Outlier

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #6 on: September 15, 2014, 07:33:07 PM »
We are going to be tackling a poured shower pan as illustrated by MMM in the "How to make a relatively sweet shower - cheap" post. My question is about the roofing paper MMM uses at the base of the shower to keep moisture from wicking into the subfloor. Since, unlike MMM, we don't happen to have spare roofing paper, we would like to avoid the added expense of purchasing some and are looking for alternatives.

Our thinking is that something as simple as laying down contact paper on the wood might work. Or even stapling parchment paper or wax paper? Another thought we had was Redgarding the subfloor where the shower will be, but that seems like overkill if it's just moisture wiking we're trying to avoid. Maybe it's even ok to skip that step? I'd love to hear from people who have made the poured shower or contractors who might know what's best.

I actually just poured a shower pan at my house two weeks ago, so this is fresh for me.  It's okay to pour your mortar bed right on a plywood subfloor (not okay if you have OSB), but better if you can use a slip sheet.  Tar paper is okay (like MMM), or you can use 6 mil plastic sheeting.  Neither one is very expensive, and for something like a mortar bed (where mistakes are not easily undone), I'd rather do it right the first time if I were you.

Not sure if you bought the Redgard yet, but that stuff is super expensive, and would definitely be overkill for a slip sheet.

Good luck, post some pictures when you're done!

Contractor garbage bags that home depot sells for construction projects are 6 mil plastic. It says so right on the side of the box. Those things are thicker than the rolls of painters plastic tarp. I bet a contractor bag cut on the seams would work perfect. I'd buy a box of them and just two for this project and keep the rest around.

They're super handy when you want to throw out lots of heavy or pointy trash.

Primm

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #7 on: September 15, 2014, 07:35:45 PM »
Yeah, don't know why I didn't think of the plastic sheeting, guess I was thinking of things that would be flat to the floor or even stick to the floor. That's a good idea!

Pour a slab of concrete onto a plastic sheet and it will very quickly be flat to the floor. :)

Good luck, and agree with posting pictures. I might be interested in doing something like this down the track when we finally do our bathroom as well. :)

FIence!

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #8 on: September 16, 2014, 07:54:52 AM »
Yes, right as soon as I posted I thought to myself, I think almost anything would be flat to the floor once we pour concrete on it. :)

I just saw those contractor bags in a store ad and noticed the thickness... we might go ahead and go with that.

Thanks to all for the advice! Once we get this thing poured/dried up I'll post about it!

b4u2

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #9 on: December 10, 2014, 11:58:37 AM »
I am going to be doing this soon. I just bought the last of my materials now just need to start tearing out the sheetrock and neoangle shower. Little nervous doing this but watching lots of Youtube videos and writing out the steps I need to finish things in order. I will be using 6 mil plastic sheet under the shower pan.

kendallf

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #10 on: December 15, 2014, 07:12:06 PM »
I did one from scratch earlier this year; really wasn't a big deal.  I did not Redgard the pan and curb; I decided to go ahead and build an old school one with a preslope, liner, mortar over that, et cetera.  It was very cheap in materials cost and I figured it'd be more forgiving of beginner mistakes.

The only thing I'd be wary of with MMM's method is the seam between the walls and the floor.  I would at least tape those seams with the fiberglass tape and thinset, then use the Redgard.  I believe there are instructions for doing this on the Redgard site.  Maybe MMM does this but it wasn't clear from his article.

FIence!

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #11 on: December 17, 2014, 12:09:53 PM »
So just a quick update over here. We did use the 6mil plastic sheeting, and I can verify it worked... because we were so unhappy with the dried surface that we decided to chisel it up and re-do it. The plywood subfloor didn't have any water damage, so for the purposes of a water barrier it worked! (There actually was one very small water blossom on the wood, that was from where we screwed through the sheet putting the lip form down. But it was small, and was completely dry, just a stain.)

If anyone attempts one of these and isn't happy with the slope or surface, let me assure you that it is genuinely fun to break one of these up and remove it.

b4u2

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #12 on: December 17, 2014, 01:30:15 PM »
I have torn the sheetrock out and getting ready to remove shower. Now that I am down to the studs just curious. Do I need to put blocks between the studs if I run the cement board all the way to the floor? I am going to put the board up before I pour the shower pan. Trying to see if I can save some time and board cuts.

Greg

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #13 on: December 17, 2014, 02:40:07 PM »
It's best to fully back the cement board edges, so I would if I were you.  At the top it's not as important, very little chance of impact/side load up there.  At the bottom it will get kicked and pushed against during cleaning etc.  Stronger is better when it comes to tile backing.

JackofAll

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #14 on: December 18, 2014, 09:19:41 AM »
All these shortcuts I hear scare me.  No matter how much waterproofing is done on the surface of the poured pan, some water will weep down either near the drain or through the concrete itself.  Concrete is porous, grout is porous, and wood loves to soak that water up and turn it into mold and mush.  I know there are other methods out there, but I prefer the method of using a pvc shower pan liner directly on the subfloor with a screw up drain.  You can notice that the screw up drain has weep holes so water that gets through the shower floor and rests on top of the liner can drain. 

The idea of pre-slope, liner, then mud bed works, but isn't entirely necessary.  Depending on building codes, the shower pan liner must go up a minimum of 2" over the top finished height of the shower curb.  Tucking the corners is tricky, but there should be absolutely no holes, cuts, or screws below 2" from the top of the curb.  The liner is installed before the backer board.(remember that it's back there when screwing on the backer board and avoid putting screws in the bottom 6" of the board)

Also, I always left at least a 3/4 " gap between the backer board and the floor pan to prevent moisture from the pan from wicking up the wall.  The tile would go all  the way to the floor, but the bottom of the backer board would never be fully submerged in water.

Hope some of this helps.

monarda

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #15 on: December 20, 2014, 10:26:10 PM »
There's a whole forum where people ask these kinds of questions all the time.
Head over there, and pros will help and advise.

http://www.johnbridge.com/vbulletin/forumdisplay.php?f=1

geekette

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #16 on: December 20, 2014, 11:56:56 PM »
Lots of great info on the John Bridge forums.  We redid our master shower about 10 years ago with info from there, although instead of a poured pan, we went with a solid surface pre pan and Kerdi on the walls.  Not the cheapest, no, but it sure works better than the old one!

b4u2

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Re: Poured shower pan (AKA "Relatively Sweet Shower") help
« Reply #17 on: December 21, 2014, 05:31:21 AM »
I just poured my curb last night. I did a rather dry mix so I am hoping it sets up well. Will be giving it plenty of time to cure since I can't work on the actual pan for a few days.

Basically all finished now. I did have a shower head leak at the pex connection so I had to remove a tile on the wall. It wasn't fun. Not sure what happened because I tested the lines before I put the tile up and it never leaked. Luckily I caught it early.

We did ours with 2 shower heads, one on each wall with separate controls, and we really like it. One is a rainfall type and the other is a standard shower head. Slate is on the floor and feels really solid and not slippery at all. The walls are generic tiles from Lowes with glass tiles to break it up and add some style to it. We currently are using a bar and curtain but will be looking for a sliding glass door to go on it.
« Last Edit: January 15, 2015, 10:38:24 AM by b4u2 »