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04-28-2015, 01:43 PM
This site helped me rebuild a shower several years ago, and it is awesome! So now that I've been in a different house with another pitiful shower circa 1990, I'm at it again.
Our previous project just involved gutting the existing shower and building it out from the studs, replacing the existing drain and redoing the pan, etc. I can do that in this house and would need to also raise the ceiling, which I believe I can do, given that there is space above it to do so.
HOWEVER, I have thought this shower space a bit cramped from side to side, at only 33" (length is fine at 58"), especially since the shower head is on the long wall (door on the short wall). And I know that more open showers are more highly valued these days - and in its existing location, that's simply not possible.
So today, a wild thought entered my mind, and I googled it, and lo and behold, there were beautiful examples of tubs INSIDE the shower space. ( ) On another wall of the bathroom, we have a jetted tub we rarely use, and it takes up a lot of space, plus there's the unused space in front of it used to access it. I have the room there to replace the tub with a smaller one (like a claw foot) and locate the shower in front of the tub, with the entire wet zone enclosed behind glass. It would not only give us more room for the shower but also the space that is currently the shower could be converted to additional closet space. The wet zone would measure about 80" deep by 60" wide. I'm attaching pictures showing the existing tub area. The closet door to the left would be closed in. The existing shower door, right next to the closet door, would become the closet door.
So here is my first set of questions, I am sure, eventually, of many. How can I deal with drainage? Can the shower drain tap into the existing drain pipe for the tub fairly directly? That may sound like a really elementary question, but as I said, my previous project was a rebuild in an existing location. Similarly, can I tap the existing supply lines for the tub for the shower? I would have them on the same wall (on the right side), which is also where the existing tub drain is.
ANY thoughts or info is appreciated. Thanks.

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04-28-2015, 07:02 PM
Hi Alison, welcome back. :)

I think you'll need a considerably larger area to pull off the shower / tub arrangement you want. The example you provided is around 7'x12' which is about 2.5 time the size of the target 7.5' x 5' space you've identified.

For example, the freestanding tub will take a minimum of 30x60 plus 3" on all side so you'd need to orient it the long way in the area leaving you only 24" remaining of the 60" width. This would be great for the tub alone but is a non starter for a adjacent shower which requires a minimum of 30" with a few exceptions.

04-28-2015, 08:12 PM
Thanks for the reply!
I may not have made myself clear that the replacement tub would stay in the same orientation against the window wall, leaving a space of about 60" x 44" for the shower. I felt that would be enough space. I was thinking either a smaller alcove tub or a 54-57" claw foot tub.
The link I provided showed several pictures, just for the concept, but I didn't have a specific one in mind that I would copy. There are a couple of pictures on that page further down that utilize the concept in a smaller space.

04-29-2015, 06:02 AM
That's certainly a better size. The entire area would need to be treated as a wet area with a minimum drop of 2" from the entrance to the drain.

This discussion has come up before and it was recommended that the drain for the tub be configured to drain out onto the shower floor.

A mud floor may be the best way to build the floor out with the required slope; are you wanting a curbless entry? If so you'll need to recess the floor to allow for the proper drainage slope.

Otherwise you can use a standard curb style with glass partition similar to the example you provided.

04-29-2015, 07:37 AM
As I was pondering all of this for hours while I was trying to sleep last night, the thought occurred to me about draining the tub onto the floor! It's amazing to see you have that as a suggestion. It's certainly clever and efficient.
Yes, I was planning on the entire area being a wet zone, sloped from the back wall, so the tub may as well drain onto the floor, especially if we go with a clawfoot. And I am planning on a curb and a mud floor because I don't particularly want to mess with the foundation. That's assuming a clawfoot tub full of water would be ok on a mud base. (?)
I'd tile all the way up to the bottom of the window.
I have uploaded a diagram of the existing bathroom layout, with the shower to the left, and the proposed design, with the shower area in front of a smaller tub.

04-29-2015, 09:12 AM
Sounds like a plan. You'll need about a 1/2" shim under the legs the one side of the tub to offset the floor slope but that's a simple todo.

Are you keeping the fancy chandelier? :D

Have you checked the deflection rating of the existing joist structure?

04-29-2015, 10:53 AM
This is a concrete slab, so the deflection rating/joists issue is moot. Unless you're talking about the plan to remove the wall between the shower and closet? This is a two-story house, but there is nothing above this entire space.

The chandelier... that was a previous owner install. :uhh: I will probably replace it when I do work in the vanity area and replace the other light fixtures! I don't love it but I don't hate it, but I think its future is very dim. :lol2:

Now, I just need to figure out the water supply. What is the best way to move them over about 30"-32" from where they currently supply the tub? Can I just elbow them over and drill my way through a couple of studs? I am thinking it would be nice to have everything on one system. The current supply is about where the shower head would go, actually, but since no one wants to get out of the tub to add more water or turn on a handheld shower, I'm going to have to move things over: with a wall-mounted faucet, handle and diverter at the tub, then going back to a shower head/handheld combo controlled by the tub diverter. That way I can just have one handheld shower for the entire space. I suppose if I had to have two separate systems/controls, I would need to have the handheld at the tub and a separate handle and showerhead for the shower... and if we wanted to use the handheld while taking a shower, we'd turn on the tub and diverter to use it. But I'd prefer to simplify, if possible.
I haven't opened up that wall yet to see what everything looks like regarding the supply lines. I want to make sure I'm comfortable with my entire plan first. But there is an access panel in my closet (to the right of my diagram) right at the drain, and from there I can just make out parts of the shut-off valves and the tubing used for the supply lines.


04-29-2015, 12:02 PM
Sounds like a nice plan to expand the wet area.

As to moving plumbing, that is how it is done. Tap off what you've got and snake it to where you want it. Using PEX might make things easier although I personally prefer to sweat copper.

You do need to think about control access a bit since to get to the tub, one must go through the shower.

You may also need to think about the DWV (Drain Waste Vent) system for the new shower. You can probably directly tie into the drain for the tub and use its vent but I'm not well-versed in the plumbing codes for drain and vents.

You might need to make the "plumbing wall" a 2x6 wall to handle all of this stuff so keep that in mind. It just depends on what kind of room you have. Are any of these walls load-bearing?

04-29-2015, 12:33 PM
Thanks for the reply and the additional things to think about!
I don't mind the access through the shower to the tub. Given the closet of a shower we have now, this would be a good trade off, especially since we rarely use the tub anyway.
PC7060 had a good recommendation earlier regarding the drain, to have the tub drain into the shower floor... and that works well for this plan, because I won't even have to move the existing drain location... just convert it from its tub assembly to a proper shower assembly. That way, I don't have to have two drains.
As to load-bearing, no.
A plumbing wall wouldn't be too much of an issue since the back of that wall is just the inside of a closet.

04-29-2015, 03:22 PM
I'm not quite envisioning how emptying the tub water onto the shower floor will look because you would have to deal with properly sloping the mud bed to the drain which will be under the tub...right? :uhh:

How might you service the drain if it is blocked by the tub? You'd also have to deal with leveling the tub on the sloped floor. Should a mud bed be used under a tub like that?

I guess I'd need to see more about the design or understand better how this might work and look because I'm missing something here. :)

04-29-2015, 04:22 PM
Completely missed the slab on grade comment, my bad.

Chris - Re the drain blockage under the tub, I'm envisioning this is a free standing unit like a mini claw foot.

If it's a full apron tub, I'd just run it in to a standard p-trap drain line like a regular tub setup. You should be able to seal the penetration through the mud bed with a elastic gasket similar to the Kerdi gaskets.

04-29-2015, 05:23 PM
Yes, I understood the same thing, that a clawfoot would be essential for that drain plan, and luckily, that is what I am leaning toward anyway.:shades:

04-29-2015, 05:32 PM
Good deal, I think the claw foot will look really cool in that layout; combined with the glass panels you'll have a unique mixed retro/modern look.

04-29-2015, 06:52 PM
Oh, and the tub wouldn't be over the drain. The drain is about halfway along that wall. The tub would be off to the side by several inches. There is a clawfoot tub I was eyeing that had levelers... I'm assuming it would give me the half inch or so I need to adjust for the slope.
But I did have the same question about putting the tub on the mud bed. I know that or something similar has got to work because there was that entire webpage full of beautiful examples, all with a tub sitting right there in the wet zone.
If you see the previous diagram I posted... I did revise it to clarify the true drain location. Here that is.

04-29-2015, 08:21 PM
Okay, cool...I got it AND it is pretty cool idea albeit a bit strange just to empty the tub right onto the floor! :crazy:

Would you go with floor-mounted hardware for the tub then? You have room? Or being a wet area, I guess wall-mounted would be best.

Also think about cleaning around the won't be fun but be sure you have reasonable room around it.

Slope to your drain needs to be a minimum of 1/4" per 12" so I wonder if the leveling system for your tub can accommodate that. You'll need to measure the distance from the drain to the furthest tub leg and you should get a rough idea of the adjustment you'll need for the tub. It sounds like it'll be more than a 1/2" as I think it'll be longer than 24" from drain to far leg...probably more like 36 - 48".

04-30-2015, 08:00 AM
Yes, wall mounted hardware is the plan.
As for the slope, I believe I only need to accommodate whatever slope there is between one clawfoot and the next. Based on the measurements and calculations I made, I will need to adjust the rear right leg and the front left leg down by about .25" and the front right leg by about .5". That shouldn't be too bad.

Will a cast iron tub be an issue? Most tubs in the size I need are cast iron, especially the slipper style, which I prefer... whereas the acrylics are in the larger sizes predominantly. I do know about a standard (non-slipper) acrylic 57" tub, but I think I'd like a slipper style.

05-03-2015, 04:47 PM
Per my previous post, I did find an acrylic tub in the style I like, so that helps alleviate worries about the weight of cast iron.

PC, you had mentioned that the tub draining onto the shower floor had been discussed previously in this forum as a solution. I did some searching and could not find it. Do you have any hints as to how to find those threads? I'd like to see that project and see if there is anything to learn from it. Did you post on that and do you know of any key words I can use to search?


05-03-2015, 05:39 PM
It was discussed in general terms only but there is nothing complicated about it. Should be pretty simple since the fawcets connections will be wall mounted. Regarding cast iron or acrylic, that's dealers choice.

Treat the entire area as a water proof wet area with tile before placing the tub. Use a standard drain fitting in the tub with a short drain neck fitting to take the water down to about 1" above the floor.

I would not worry about lowering the high side of the tub just shim the low side up. Cut a 2cm piece of marble or granite into a square or rectangle around the size of the foot or a little bigger and do the fine leveling with grout to set the spacer in place (semi permanently) once you have the tub where you want it.

05-08-2015, 04:32 PM
I was using another site to post a question about the framing aspect of our overall plan, and a responder said to take into consideration the fact that tubs require 1.5" drains, whereas showers require 2" drains. Can someone tell me more about this requirement? I'm really not wanting to demolish a good portion of our slab for the purpose of putting our shower where our tub is now.

I'm hopeful that this is not the entire pipe needing to be 2"?

Freaking out a little right now. At least I haven't demolished anything yet.

05-08-2015, 05:29 PM
You may wish to dig into the local plumbing codes in your area to see what is what. Do you plan to gets permits and such and have inspections of your remodel? That might also influence your design. :)

If the code and inspector require 2", it WILL have to be 2" all the way to the stack so that would be a buncha concrete busting up for you. Not fun but certainly doable with the right tools.

Were it mine, 1.5" would suffice and no city officials would be checking up on it. :D

05-08-2015, 06:34 PM
I just checked the IPC 2012, and section 417 says that shower waste outlets can be 1.5"... just as with tubs in section 407. Can anyone confirm this?

And I don't currently plan on inviting anyone for a visit. :D

05-08-2015, 07:01 PM
The drain size is based on max flow, I have a double shower that I ran the numbers on to confirm the use of 1.5 drain, see below.

Chapter 7 Sanitary Drainage of the the Virginia 2009 IPC Table 709.1 allows the use of a 1.5" for showers with a total flow rate of less than 5.7 GPM for all shower heads and body sprays. The two units I am using are 2.5 each (5 GPM total) so I am good to go with the 1.5" line.

05-08-2015, 09:36 PM
Good to know... but I'm not sure how the tub draining into the same drain would affect someone's assessment. For example, it is possible that a person could have taken a bath and be draining the tub - while starting up the shower at the same time, such as to wash hair.

I'm not sure how to calculate GPM for that scenario, which would be the worst case. In most instances, we'll just use one or the other at a time, but since they will drain into the same drain, I'm still pondering.

05-08-2015, 09:52 PM
No problem, drain from the tub doesn't factor in. Calculate the total flow from the combination of both faucets; typically 2.5 - 3 GPM each. Keep the total number of 5.7 GPM in mind when selecting the fixtures.

You'll be fine either way, that 1.5" drain line will easily keep up with both sources.

05-12-2015, 10:19 AM
Unfortunately, it seems that tub faucets average 5-6 gpm just by themselves. So that plus the 2.5 from the shower head puts me over 5.7 gpm. :bang:

The stack is really close by, but this puts me into the unhappy zone.

Wait... does the stack have to be replaced, too? It's also 1.5". Waaa!

05-12-2015, 12:22 PM
I think I may have a way around the GPM and Drainage Fixture Unit problem posed by having separate tub and shower faucets... combine them. (See my earlier post from today.)

How would it be if I selected a standard tub/shower faucet combo with diverter? They'd be right next to each other, so no big deal to turn the tub on first and then a diverter to activate the showerhead. The showerhead just wouldn't be straight above the tub... it would be over to the right a couple of feet.

Downside is I wouldn't get my cool clawfoot tub faucet I've had my eye on, but if I am seeing things right, it would solve all my problems and I wouldn't have to mess with any of the drain or vent piping.

Would this work?

05-12-2015, 01:13 PM
You can put the diverter valve (sometimes called a transfer valve) anywhere you want that is convenient to your situation and that looks good to your eye.

Some tub fillers have that little knob on top that acts to divert the water from the shower head to the tub fill valve. I guess yours either won't work or you simply get one without such a knob.

Now you can't fill your tub and have the shower head on at the same time if you go this route. Probably not a big deal, I think.

05-12-2015, 01:25 PM
This is the faucet I was considering, and it does have a diverter valve but only for a hand shower. Perhaps there is a way to run matching nickel piping back into the wall from that diverter over to the shower head location, but it might look a little odd... so I'm thinking the other way might be best.

Most of the clawfoot tub fillers that I've seen with a regular diverter have not only a shower head but also the big ring for the shower curtain, so I'd be buying a bunch of stuff I won't need.

I'm thinking that running the tub at the same time as the shower is not a problem at all, if it saves me the trouble of busting up my slab.

05-12-2015, 02:10 PM
Well, it is your bathroom but controlling the hot 'n cold mix from the tub faucets for the shower head that is NOT located in the tub is a bit strange but if they are reasonably close, I suppose it could work. Like in real estate, it is location, location, location so plan carefully and think it through.

You'll reach over the tub to turn on the hot and cold water and wait until the temp is nice. In the meantime, the tub will be draining water possibly down by your feet until the temp is right. Now you turn the diverter and the shower head comes on. Initially, it will be a tad cold as the water sitting in the lines gets flushed out with the warmer water. Now you shower and when done, you must reach over the tub again to turn both valves off or both at the same time so you don't get scalded with hot or frozen with cold water.

If you skip the fancy tub filler you're looking at there and go with a 'shower only' approach, you'll have a single hot/cold mix valve on the wall and a diverter on the wall...perhaps equidistant between the tub and the shower head. Then for your tub, you'll only have a single tub filler protruding from the wall. Now adjusting the water for the tub might be a pain now but everything is on the wall and all plumbing is hidden. Hmmmm, but now you cannot adjust the water while in the tub or add more while in the tub...unless you locate the mixer within reach.

Well, there is a lot to think about with this unusual setup. I look forward to your build to see how you situate things!

05-12-2015, 04:22 PM
Actually, in the time I spent away from the computer, I had decided on what you'd laid out in your third paragraph there. I'll need to have everything controlled off a valve close to the shower head, with a diverter that can send water to the tub and a handheld shower. The trick, though, is finding all those components that match. That's what I'm having trouble finding. If anyone knows a good source for fixtures other than the usual box stores...

05-12-2015, 04:50 PM
Try here (

I've placed orders for several thousands of dollars worth of bathroom crap from that place. They seem to have the best prices and ship quickly. You ought to be able to find what you want there.

If you check the link below my sig, all the pretty plumbing type stuff in my remodel is from that place. :)

05-15-2015, 02:54 PM
I've been trying to figure out plumbing fixtures and did a bit of a circle. I thought I had the 1.5" drain issue figured out when I planned to go with a single mixer valve. But then my plan turned into the attached. I'm thinking I'm not going to be able to do this with a 1.5" drain.

Am I unfortunately correct?

What I don't understand, though, is that some people have a regular shower head, a hand shower and a tub spout INSIDE A TUB and I'm guessing that's fine and in code. But because I've got mine spread out over an entire wet zone, then I'm in trouble? Really?

The diverter I've found has three ports, and while I probably won't ever use two fixtures at the same time, it has that capability. So, for example, the theory is that someone could be filling a tub and using the shower at the same time, say, to wash hair before getting in the tub. That could be in the range of 7.5+ GPM.

Maybe the saving grace of people using a standard shower-IN-the-tub set-up is that the diverter spout means they will never be using both the tub and the shower at the same time. I'd really appreciate some ideas at this point. Would I be ok if I just skipped the separate handshower and got one of those 2-in-1 Delta In2ition shower heads instead? Or am I destined to either tear up my home's foundation or compromise on what I want? Is there a way to configure this to be ok with an existing 1.5" drain as would be ok with a tub and overhead shower?

05-15-2015, 05:11 PM

Given the problems the 1.5 inch drain is causing I'd give serious thought to just adding 2" line and connect it up to the 3" terlet line. How far from the planned shower is the toilet?

Based on the scale of the overall project this is a pretty simple task.

05-15-2015, 05:25 PM
Thinking in terms of everything running first, you can only have two devices on at one time and the flow to those two devices gets split so I wonder if the the same flow rate applies?

In my shower, I can run the shower head and the hand held shower at the same time and the flow to both, while decreased compared to one at a time, is actually fine.

I didn't dig into what kind of diverter valve you have but if you want to run 3 devices with it, I'm guessing you can only run one at a time. For my Kohler diverter/transfer valve, this was the case: run 3 devices, one at a time or run 2 devices one a time or both together.

Now your mixer valve (again, didn't dig into it) can likely, by itself, run two devices assuming one is a tub filler due to its own diverter valve. From your mixer, you run a line to the tub filler and a line to the shower head. Now the line going to the shower head will connect to the separate diverter/transfer valve in which you can select either the shower head or the hand held shower (or perhaps both). Either way, you can only run the tub filler or run the transfer valve (which allows solo action or dual action for the shower head and hand held shower).

Now your main concern, I think, and that is when you empty the water from your devices: tub, shower head and hand held shower. I could see the tub being filled first (which means nothing else is running) and then turning that off and running the shower head and/or hand held shower. Now the tub could, theoretically, be emptied while the shower head and/or hand held shower are running and thus your concern about adequate drainage with a 1.5" drain pipe.

Well, if you aren't getting things inspected, I think you'll probably be okay as things may simply drain slowly...maybe more slowly that you care, however. The bottom line is this: a 2" pipe will drain about TWICE as much water as a 1.5" pipe in terms of GPM. Now how likely will you need to drain so much water? Further, it is a situation that can be prevented by the operator rather easily and simply, right?

05-15-2015, 06:32 PM
PC, I think I've come to peace with digging up that pipe.
And Chris, what you describe is true if I were running the mixer straight down to the tub first and then diverting it there to the shower head, but I was hoping to avoid that. I certainly can do that, and have thought of it as an option that would enable me to keep the drain intact. However, Delta is very explicit that the tub spout should be run straight down from the mixer valve, and I wouldn't want to have to put the mixer right over thee tub spout in my configuration.
I'm lucky that only a few inches of concrete will have to be jackhammered up. I've done it before; I can do it again. The stack is actually just a few inches away from the existing tub drain. The stack for the bathroom group comes up from the other side of the bathroom, and then those two join together in the attic.

05-15-2015, 06:43 PM
Oh, and the diverter can run any two fixtures at the same time... tub, shower and hand shower.
You're right, Chris, that it is up to the operator to not cause problems, but as I don't plan to die in this house, I'm thinking ahead to what a home inspector might say at the time of selling (years down the line) if we have everything on such a small drain. Better now than later.

05-21-2015, 10:40 AM
:sick:I have begun demo and got enough drywall off to discover the stack from the planned wet zone drain, which I was going to upsize from 1.5" to 2" takes a detour across the wall and around a corner to an exterior wall. I'm attaching a diagram and a picture of the space in the attic were it comes out.

The left-most part of the wall is actually reinforced with a series of studs... one parallel to the wall and one regular stud on each side of it. That's because of an architectural feature I need not bore you with. So that's the corner where the drain takes a turn. That's the first problem.

The second problem is that where it comes out in the top plate is basically inaccessible. Even if the 2x4 that's there were a 2x6 with enough wood to let me widen the hole for a 2" PVC stack, there wouldn't really be enough room for me to actually get a drill or anything else in there to make it happen.

I'm not sure why the plumber routed it this way instead of in the interior wall, but I guess the why doesn't matter. I just need to know
1. if anyone has any suggestions on how to tackle this - if it is even possible at all... and
2. Whether there is a point in the line when I can just leave it at the 1.5" because I'm thinking I'm not going to successfully get this crazy thing out and replaced.

Keep in mind I would be ok with constructing something to house a different route because the back of that wall is just my closet, so I can put a soffit type space in there if I need to... but I wasn't sure whether relocating the run was a good idea.

05-21-2015, 11:07 AM
Alison, by "stack" are you referring only to that vent pipe?

05-21-2015, 11:16 AM
Yes, CX, that's what I mean. Maybe using the wrong terminology - it is a branch that goes up to an actual main stack vent that goes to the roof elsewhere in the attic.

Per the post just above, I've learned a bit more. The second 2x4 (blue arrow) appears to be the stud for the back closet wall/exterior wall... so I don't have to mess with that 2x8 just beyond it. (Originally thought it was and referred to it as another 2x4 but just went in to look at it again.)

The red arrow indicates the measurement where the corresponding space on the other side of the wall (closet) ends.

So unless that stud for the back of my closet (blue arrow) has another one right next to it for any reason I MAY actually be able to finagle it out and another in...

HOWEVER, I don't know how anyone could successfully install a 2" pipe through a stud and actually have any WOOD left on either side of the hole. The holes in there right now are as big as I would ever want to go, and a 2" PVC pipe would MAYBE JUST FIT with no wiggle room - and no room at all for the elbows and other fittings which have an even wider diameter.

So again, what the heck am I to do?

05-21-2015, 11:21 AM
Alison, forgive me if this is a stupid question, I haven't taken the time to go through the entire thread, but other than not being able to get to the top plate directly above, what keeps you from cutting the vent where it's reduced to 2" and going straight up with it?

There are bits made just for that purpose that will make a 2 1/2" hole through the top of that wall. That would be the size I'd want the hole, even though it would leave only 1/2" of wood on either side. A 2" pipe would be 2 1/4" total diameter including the pipe walls, so a 2 1/2" hole would leave a tiny bit of wiggle room if needed.

05-21-2015, 11:28 AM
Kevin, let me clarify that vent is 1.5" all the way into the attic until the branch joins a 2" vent elsewhere in the attic... it is not reduced to 2" from something larger... in fact, I am needing to enlarge from 1.5" to 2". It may look like the PVC is larger toward the bottom, but those are just some couplings they used to tweak the position.

I wouldn't have a problem with sending it straight up instead of having it elbow, go across the wall, elbow again through the corner and then go up the perpendicular wall, which I think is crazy to begin with. You can see from my first post of today with the attic picture that the PVC runs right back by the same area it diverted around to begin with.

But I have to think it was originally done this way for a reason... though I don't know what it could be unless it is because there is a single electric line going across the wall a couple of feet above it... but I wouldn't think that would be the real reason, if there is any logic to it.

So I'm not sure what to do.

05-21-2015, 11:39 AM
I see that now with the 1 1/2" coming up from the slab. I though there was a reducer there. So if you can get it increased to 2" up to that point, then check all the way up inside that wall and make sure there are no obstructions. Check in the attic as well, as much as you can, to make sure you won't have problems there.

I can't tell you why someone would bend that vent in three different directions rather than going straight up. Makes no sense to me either. You may find out why as you continue your demolition/investigation. Then again, you may just lay in bed all night wondering about it. :D

05-21-2015, 11:44 AM
The attic IS the main obstruction - because the pipe emerges in an eave with a hole too small for a 2" pipe and no way for me to cut it bigger. The holes in the studs there are larger than the one in the attic for some reason. The one on the top plate is very snug against the 1.5" pipe. And I have no room to work in. Unless I take the roof off.:crazy:

See my post from 11:40 for more on that, and there's a picture somewhere here, too. It doesn't show how inaccessible it is, but trust me.

I'd really rather just go straight up. There don't appear to be any obstructions. I am just perplexed as to why it wasn't done that way to begin with - and if there was a reason, I need to figure it out because it might mean I shouldn't do it differently.

05-21-2015, 11:52 AM
Oh, and again, I'd never be able to fit an elbow for a 2" pipe through the stud, because that's even bigger.

Is there a reason not to go straight up?

05-21-2015, 12:00 PM
Make your drain 2" as you want to but leave the vent alone or make the vent 2" as far as your sanity will take you and then connect it to the smaller 1.5" pipe.

Since you're not getting inspections, I think this will be okay and it isn't going to explode (or implode :D ) your house or anything nor will there be a 100 year flood caused from it or anything. :cool:

OR do not try to connect the new 2" vent to 1.5" at all...just vent this on its own if possible and if that is easier.

05-21-2015, 12:07 PM
Well, I thought about leaving the 1.5" vent intact but ADDING a 2" vent to it. I could T it where it bends, leaving the 1.5" vent alone and taking the new 2" vent straight up and adding it like a new branch to the same main vent.

Would that work?

Or I could even just add a second SMALLER vent? Because it's already got 1.5"? No need to add 2" for a total of 3.5" venting? Or is that not how it works?

Or I could replace all of it where I can get to it, but that would mean the area that comes through the top plate in the attic would stay 1.5". I could even make it 2" after that... but I really don't think I can do anything about that eave area.

05-21-2015, 12:21 PM
Alison, where did you find the requirement for a 2" vent? That size is typically required for venting 3" wet lines. I'd think a 1.5" vent is fine for a single 2" drain line.

05-21-2015, 12:30 PM
Well, PC, YOUR post to this thread on 5/15 says


Given the problems the 1.5 inch drain is causing I'd give serious thought to just adding 2" line and connect it up to the 3" terlet line. How far from the planned shower is the toilet?

Based on the scale of the overall project this is a pretty simple task.


Given this and other info out there in web world, I surmised that a 2" drain required a 2" vent.

05-21-2015, 12:30 PM
Well, I thought about leaving the 1.5" vent intact but ADDING a 2" vent to it. I could T it where it bends, leaving the 1.5" vent alone and taking the new 2" vent straight up and adding it like a new branch to the same main vent.

On this thought train, I think I would just skip the 1.5" altogether and pretend like it doesn't exist and vent the 2" where convenient.

Or I could replace all of it where I can get to it, but that would mean the area that comes through the top plate in the attic would stay 1.5". I could even make it 2" after that... but I really don't think I can do anything about that eave area.

Like I said about your sanity....

There is a plumbing forum called Terry Love. You might try posting over there regarding your plumbing/venting concerns since that is actually a plumbing forum and well regarded from what I've heard. See what they think.

05-21-2015, 12:45 PM
Good point, PC. I just did some internet searching on this and I think the 1.5" vent pipe in Alison's case is likely to be just fine. 1.5" is a very common vent pipe and for a single device, the norm. Actually, 1.25" use to be the norm but that is getting rarer and rarer and 1.5" is actually cheaper.

05-21-2015, 01:09 PM
But Chris, this is two devices... a clawfoot tub that empties onto the shower floor. See page 1 and 2 of thread as a refresher if you'd like. That puts GPM at 7.7-8.7 or somewhere in that range with the tub filler and shower head. So two inch drain... two inch vent

And PC, I neglected to read the last part of your post. That would be great if 1.5" were sufficient for a single 2" drain for tub/shower combo. I had gotten myself pretty acquainted with the IPC's chapter 7 to verify the 2" drain size, but I haven't stumbled on code for vent size.

05-21-2015, 01:33 PM
OMG, does this save me?
I have a total of 4 fixture units and the vent stack runs way less than 150 feet.

05-21-2015, 01:35 PM
The file didn't attach in previous post... so here again, does this save me? IPC chapter 9...

05-21-2015, 02:55 PM
Yep, that's it. You'll be fine with 1 1/2" vent.

How far is the existing vent through the roof from where this will come up? You can tie into that (see below for example) to avoid running another line though the roof. A word of caution though, the existing lines can be a little fragile if they've been exposed to attic temperatures for 20+ years. Try not to bang 'em around when cutting in for the new vent.


05-21-2015, 03:00 PM
If I am fine with the existing 1.5" then I won't need to mess with any of the vent or tie a new one in, per:

Yep, that's it. You'll be fine with 1 1/2" vent.

How far is the existing vent through the roof from where this will come up? You can tie into that to avoid running another line though the roof.


I can just replace the drain and move on with my life?

Man, I lost a whole day to researching this! I could have been whacking that cultured marble tub with the 12 pound sledge hammer! :D

But just to answer your question, I'd say after going up into the attic space, that goes over about 7 feet maybe, then up a few feet and directly into a main stack vent that jogs over and out the roof... maybe a total of 20-25 feet at most, including horizontal and vertical from entry into the attic to the roof. Had I needed to run a new branch, I would have tied it into that same vent that goes to the roof. But I don't actually need to do that, right?

05-21-2015, 05:25 PM
Yes, your correct, I thought this was a new drain line.

Time to git out the 'sledge!

05-22-2015, 10:57 AM
Vents are a big strange mystery for sure! :bonk: :scratch: :wtf: :crazy:

05-23-2015, 10:14 AM
I got the existing tub drain partly excavated this morning, just enough to see what's what. Due to the depth and the length the trap jogs over under the slab, I don't have a line of sight to the part of the vent stack where the trap meets it, but I can get a camera down in there and snapped this picture. A few things concern me...

Firstly, I think I will have no room to cut anything unless I jackhammer up the slab a bit. As indicated on the picture, the far side of the stack is only about 12" from the edge of the foundation. Is it still safe to take out that wedge of slab marked in blue? Or should I try to cut the drain without doing that by excavating as much dirt as possible? (which may be just as problematic to a foundation?)

And I've usually cut pipe with a hacksaw. I'm sure I'll need something smaller. Anyone have good luck with something that will cut in tight spaces?

Additionally, remember, I'm going from a 1.5" drain on a 1.5" stack to a 2" drain on a 1.5" stack. Given that, can I do a reducer BEFORE THE TEE connecting the trap with the stack? Or do I HAVE to cut the tee of the stack out and replace it too? I figured I could do a reducer before the tee since it's reducing there anyway but wanted to get some feedback.

I'll probably post at Terry Love about this, too, but wanted some feedback from folks who know where I'm going with this.

05-23-2015, 10:40 AM
Alison, the part you have circled in blue is 2" pipe, is that correct?

As a general - hard and fast general - rule you may never reduce the size of a drain pipe along its flow. You may increase the size in most cases, but you may never reduce it even if the reduced size would have been adequate for the entire run.

My opinion; worth price charged.

05-23-2015, 11:36 AM
Thanks, CX.

In the meantime I have learned two things...

The first is that the waste line runs right back by that trap. I am wondering if I have the option to tee into that waste line and run up a new section of the vent. It would mean any slab demo would be more in front of the drain instead of to the left, close to the edge of the foundation

THEN I realized that the drain actually transitions to 2" before the trap!

So I think given these two things, I definitely don't have to replace the T on the vent stack... just replace things over from there to the shower drain.


05-23-2015, 01:12 PM
Problem there is that your trap will be in the wrong place when you've moved the drain to the center of your shower floor.

I think the best fix for what you've got would be to cut the trap off at the horizontal attachment to the sani-tee and cut the pipe out of the tee with a special tool made for the purpose. They're not inexpensive and you might do better hiring a plumber who is familiar with that tool to come do it on your behalf. Might be dinero well spent.

Presuming, of course, that you will have sufficient fall from the new drain location, which does not appear to me to be a problem.

My opinion; worth price charged.

05-23-2015, 02:06 PM
I wasn't planning on moving the drain to the center of the floor; I was actually planning on a linear drain along that wall. Wherever I put the drain, I'll be redoing things to put the trap in the right place. I'll therefore need to cut the existing trap off on the horizontal as you said... which won't be easy, regardless, but there is, possibly, just enough pipe between the trap and the tee to use for a new assembly. Hoping, anyway. I can at least see, and then if I need to get a plumber, she'll have things prepped quite nicely for her. :D

But I'm thinking now that the easiest thing might be to install a SECOND drain after all. Keep the one that's there now for the clawfoot (assuming I can attach a clawfoot to a clamping flange?) and install a second one to the waste line for the shower. I can tie into that vent, too. Can I do it this way, adding what I've highlighted in yellow on my drawing?

Keep in mind that I've drawn it in 2-D... the actual traps would come toward you in 3-D and things would be much more tight from side to side than what I've shown in my drawing.

05-23-2015, 04:43 PM
The linear drain seems like a reasonable solution and keeps the slope of the floor even side to side which will simply the tub installation (no left / right leveling required).

You could add a second drain for the tub if you prefer but it will complicate the water proofing if it is directly connected.

You have the right concept for the positioning of the second drain line. A pro will make short work of it, just be sure you have the drain where you want it.

Personally I'd go with Schluter (or Durock) linear drain solution.

05-24-2015, 01:28 PM
Thinking through everything again, and considering the difficulty involved with the fact that the tub I am getting will have really no wiggle room for drain alignment, I think I'm going back to the original plan for a single floor drain.

Now onto the next complication.

My stack vent coming up from the foundation is out of alignment into the shower space by .75" only at the bottom 6"... and then it straightens out behind the level of the studs. Wasn't really an issue under a tub, but it is in a shower area. Because of what I said earlier about not having wiggle room with the tub in the space, I really don't want to use furring strips to bring the whole wall out. I might not get my tub in if I do.

Then I thought about having the bottom 4" or so (the first 2" will be covered with mud) done sort of like a baseboard is on drywall - but with a 4" high bullnose. This would mean the wall would be further out just at the bottom. This might be my only option but I'm curious about the ramifications of this... such as whether it would trap water in the seam at the grout and cause mold... or any other problems... then there's the question of actually how to construct it around the obstruction.

Then I thought about an angled seat coming out at an angle from below the tub and going out to its full depth below the shower head... but is problematic for my planned linear drain on that same wall.

Any other ideas? Or feedback about my "baseboard" idea? Or is there anything else I can do to work around this? I could turn it into a little ledge for putting a foot up on - and it could function as a shampoo bottle shelf?

05-24-2015, 02:24 PM
Replying to myself just above, here is a way to envision how I could do the "baseboard" option of working around the obstruction. Feedback?

Actually, I would leave a gap at the bottom of the tile that appears to be resting on the lower Hardie and obstruction, and there are a few other details not shown correctly, but you get the idea.

I'm still trying to think through the ledge. I'm having trouble figuring out how I would work things out at the glass panels and curb on that option.

05-24-2015, 04:03 PM
That's a common problem and easy to fix with a large hammer and a few bucks worth of pvc joints. Even easier if you use a checkbook. :D

Seriously though, best to just break up the concrete in that area and move the pipe out of the way. You can use a couple 45 to bring it over where you want it. Using various trim approaches is a headache and gets pretty pricey when you factor in how many of those $10 each sections you'll need.

05-24-2015, 04:53 PM
I'd spend hundreds of dollars on trim if it meant I wasn't putting my foundation in jeopardy. Foundation issues are a particular hot button with us. I just finished sawing off the drain six inches under there with my gloved hand and a 10" hacksaw blade (no handle) because I wanted to disturb as little as possible.
I know hammering out a foot of slab probably won't do much harm, but I don't want to chance it since this is so close to the edge of the foundation. I don't want the corner of my house to break off! :crazy:
So, if you'll indulge me...

Besides, I found a good deal on trim, so it won't be that much to do.

And I'm now thinking I'm going to do a curved, very shallow, half circle foot ledge, if I can figure out how to construct it. Can I cut the Hardie board around the obstruction so that the Hardie will lie flat on the studs (PVC membrane still where it needs to be, but it will just bulge out around the obstruction)... and then construct a ledge in front of all that with bricks and mortar?

05-24-2015, 06:13 PM
Duh. :dunce:
Ok, it occurred to me that I could cut that vent stack off fairly close to the floor level (leaving enough room for couplings) and do the couplings there to shift it over low down so that the obstruction doesn't go up past the level of the mud bed. Is there anything scary about doing that? Or any reason not to do it?

05-25-2015, 07:55 AM
Alison, understand your concern re banging a hole in the slab. I don't think a small opening would cause you a problem but I can't see your house very well from here so I'm not in a position to second guess. :D

If you are going to have a plumber in to run the supply lines or set the linear drain you could always ask them. It would be pretty short work for a pro to open it up and reset the line.

Otherwise, Your idea to cut off the stack above the slab is a good one. I'd leave about 3/4" above the slab and use a couple tight turn 90 if they'd fit or 45 fittings otherwise.

How thick will the mud be be in that area? Should be the shallow end of the base I'd imagine.

PS: does that nail go into the vent line? Looks pretty close. I'd take a cutter to the nails to get the sharp point out of the way before working in the area. Or you might end up saying a few words your mother wouldn't approve of. ;)

05-25-2015, 09:12 AM
At this point I'm not seeing anything I can't do myself, so no plumber is in the plan as of yet. Unless I get into other trouble I can't get myself out of.

So I'll try the fittings closer to the slab. I can dig that down a little bit to help give some more space. I've got the jackhammer ready.

That nail isn't as close at it looks. It's from the baseboard on the wall behind, and I'll be knocking that one out!

Just for laughs or shrieks, as the case may be, check out how the shower we're getting rid of was built. There's nothing like 1990 builder craftsmanship, I guess. I have no idea why there was a gap between the green board and the liner. The shower floor is sunken, so the liner goes up high enough, but then they used mud on the walls above the floor, and it's all loose in that gap. Disgusting!

05-25-2015, 09:12 AM

05-25-2015, 09:37 AM
If you've got a jackhammer you're ready to go! If you can take out about 2-3" around the pipe you'll have plenty of space. Just be sure to keep the bit away from the pipe. PVC is pretty tough stuff but no sense taking a risk.

Ha, you don't want to get into a contest of your crappy 90s builder versus my crappy 80s one! Nothing but the best workmanship went into my home. :bang:


05-25-2015, 11:36 AM

Now I'm wishing I had taken more pictures of my 1971 shower redo! :cry:

05-26-2015, 08:12 AM
On to the next points of pondering...

The back wall of my shower has a window high up. I removed the drywall to a height of 84.25" from the slab, which puts me about .5" below the bottom of the window sill. I was wanting to avoid constructing the shower over any part that would make any potential replacement of that window difficult to do without destroying my shower. BUT I would really like to increase the height of my tile by about 2 inches so that the tile goes up 84" from the finished shower floor. Otherwise, my showerhead will be really close to the top of the tile and I'd like for the bullnose to be above the arm of the showerhead.

My thought was... could I just leave the drywall intact at the top but still tile my top row of bullnose over it, or would that be a problem?

Secondly, you'll notice that shelf below the window. That is just the way the window is constructed, so we'll put something decorative back on it... Can I just put my Hardieboard and Redgard on that (and make sure it's pitched for water to run off)? Or do I need to be more careful about that area for any reason?

05-26-2015, 11:05 AM
1) you can certainly overlap the tile over the drywall. Scuff up the paint with medium sandpaper to ensure a good bond.

2) yes, you'll want to pitch the Kerdi board or cbu at a minimum of 1/4" per foot. Be sure to use a good water proofing method in that area as it is a common failure point.

05-27-2015, 02:46 PM
There's no time like the present when you have things gutted to 'do the right thing' to address and fix issues. Go the extra mile. Your own time is free, right? :D

Bust up that concrete and redo that whole stack and fit it nice and clean within the wall cavity and drain placed exactly where you want it. Then mix up a wheelbarrow of concrete and fill it in. I can guarantee you that this is done All...The...Time. The house won't fall in, implode, explode, or anything like that and you'll have a nice clean start to what you want.

Redgard isn't the easiest thing to use for a first-timer and if you can hang wall-paper, hanging Kerdi goes easily. Look into Kerdi and see what you think. I think it is better than any paint on membrane...especially when it comes to changes of planes in walls and niches and benches. Hardibacker is very dry and will suck moisture out of whatever is placed on it so be aware of that. Kerdi only needs plain old boring cheap white 1/2" drywall to work. :shades:

05-28-2015, 10:54 AM
Good points.

05-29-2015, 02:11 PM
We're getting up the bathroom floor tiles today. Lots of dust!

Is there any good thread on here that discusses the best way to prep a jackhammered concrete foundation for the new tile? We're getting up as much thinset as we can, but I'm sure when we finish it won't be a pristine, completely smooth surface. I think we may use 1/4" Hardie as an underlayment but would like info on how to move forward with or without that.

05-29-2015, 02:22 PM
How large of an area are you dealing with? For small areas a diamonds blade on a grinder like I've show below works pretty well. For large areas you may need a walk behind grinder.

Both are dusty so wear PPE.


05-29-2015, 02:24 PM
Follow up comment, flat is important so you may want to consider SLC over once you've got the floor as clean as you can get it.

05-29-2015, 02:33 PM
They also sell dust shrouds for grinders or you might get innovative with a cool whip container. :)

05-29-2015, 02:49 PM
We're actually almost done. I think it was about 150 square feet. At this point we're just trying to get up the last of what we can of the thinset.:bang:
The SLC was exactly what I was wondering whether we'd need to do. How thin can that stuff be? Is it easy? I've never had to use it before.

05-29-2015, 03:53 PM
SLC pours work best with multiple people and at least two: a mixer and a pourer.

But it really depends on how much you need. Contrary to the name, they do NOT self level. The slurry does requires some pushing around and massaging and such.

05-29-2015, 04:15 PM
Why do people use SLC instead of screeding out thinset into divots and low places?

05-29-2015, 04:20 PM
Thinset isn't meant for such an application. Most manufacturers will tell you that thinset should not be used to fill in any depressions greater than 1/4" however a lot of the pros here will tell you they regularly do that as they are laying tile but they don't use it as a leveling compound ahead of time.

05-29-2015, 05:58 PM
I'd say I'm within 1/4" but I'll look into SLC and pay $$$$$$$$$$$$$!

05-29-2015, 06:46 PM
I'f you are within 1/4" and below the level plane of the floor, I'd declare victory and move on. But that's just me.

I'd only use the SLC if larger area were out of plane.

05-29-2015, 07:41 PM
Perhaps it's earlier on in the thread, Alison, but what size tiles are you looking to install on the floor? Remember that tiles don't care about level but they do like flat. The size of the tile will allow us to tell you how flat your floor should be.

05-30-2015, 07:02 AM
Big... 12x 24.

05-30-2015, 09:24 AM
You want the floor to have a deviation of no more than 1/8" in 10' nor more than 1/16" in any two feet.

05-31-2015, 06:43 PM
It looks like the worst I have is 1/8" deep chip about 1" wide, so I'm not thinking this is a huge problem. Most everything else is just very negligible 1/32" bits here and there, I think.

I'm going to try to buy some of the pan supplies in the morning. On my last shower, I didn't have to join two pieces of membrane, but this is a bigger project, and I'm going to have to do that. (This is not the time to talk me into Kerdi so don't even try.)

I was thinking the joint between the two pieces of PVC membrane should run toward the drain. I just didn't want a joint to interfere with the flow going toward the drain, so that seemed logical to me. Is that right?

Secondly, am I remembering correctly that the two layers are joined with PVC cement and then rolled to get a good seal? Regular PVC cement or anything special?

05-31-2015, 06:58 PM
If that is all you have, then don't worry about it and just use thinset.

Are you putting in deck mud for your floor? Sorry, you may have discussed this earlier in the thread but I'm too lazy to go back and re-read it. :)

If you require a seam to bond the two layers of the liner, you do want that seam as far from the drain as possible. As to the 'flow' of the seam towards the drain, it really isn't that important.

Oatey has a cement specifically for this procedure and any home center is likely to carry it.

05-31-2015, 07:19 PM
If I'm going to put the seam as far away from the drain as possible then that means I will be running it the other way than I had thought... But that means any water traveling from the back of the shower has to travel over a hump caused by the seam to get to the drain, thus my question... Yes, mud.

05-31-2015, 08:13 PM
Keep the slope at a MINIMUM (you can do more) of 1/4" per foot and things will be fine. What kind of tile for the shower floor are you anticipating? If you're doing pebbles or river rock or something kinda 'tallish' like that, I've seen some of the pros suggest 3/8" per foot of slope.

05-31-2015, 08:28 PM
Some I'm doing a linear drain I'm doing large tiles there on the shower floor, too. I was planning pretty close to 3/8" slope... ish. :)

05-31-2015, 08:38 PM
Cool. We used large format for our shower floor, too. Just be careful about the slipperyness of your tile. Check it out ahead of time to be sure. Wet it and put soap on it and see how it feels. Normally, shower floors use smaller tiles with a lot of grout lines and that it itself provides purchase for one's feet to not slide.

There is even a standard that measures slipperyness but I'm not familiar with it. We went with a matte finish tile for ours and it worked out fine for us.

06-01-2015, 07:46 AM
There is even a standard that measures slipperyness but I'm not familiar with it.

The measure is called the Coefficient of Friction where 0 = no friction and 1 = max friction. This rating is typically provided for for floor tiles under Wet and Dry Static conditions along with Dynamic conditions. The dynamic rating is the important one because once you actually start slipping the COF goes way down.

The American's with Disabilities Act (ADA) recommends a COF of 0.6 or greater on flat surfaces and for people with disabilities and 0.8 on ramps and inclines but these are only the static dry conditions.

I've included a screen shot of the rating tables for the Anatolia Classic Marble series of porcelain tiles I used in my bathroom projects showing Wet COF >= .7; Dry COF >= 0.8 and Dynamic COF of >= 0.42.


The key thing to note is these rating are under optimal conditions and real world shower conditions (soap, shampoo) can greatly decrease the COF.

06-01-2015, 10:31 PM
Wow. Ok, so now I am rethinking the large tile on the shower floor. It is really good dry, but wet is iffy. Can't find a cof rating in the specs.

There is a six inch square version of the tile and a two inch mosaic. Do I really need to do the small mosaic or does the six inch size typically help enough? It is a matte tile but relatively smooth.

I understand there are also some treatments to apply to tile to reduce the problem? For the most part it sounds suspicious, but I'm curious about it.

06-01-2015, 10:40 PM
I bet 6" would be good. The key is a matte finish tile and grout lines. Your feet will feel and lock into the grout joints so I think that would be fine.

Even my large format 12x24 matte finish tiles are okay and they have a lot less grout lines than a 6x6 would.

06-02-2015, 05:03 AM

No way to increase the COF of tile without changing the look or having to repeat the applications (and I'm not sure they even work all that well). Your 6" tiles would certainly help, post a link and I'll look to see if I can find any info on COF.

If you don't mind a different look you could always put down non-skid, the stuff they use on aircraft carrier decks. :D

06-02-2015, 09:38 AM
I'm thinking I'm going to change to the small mosaic. It was really pretty and if I use good grout, then hopefully it won't be too much maintenance.

On to the next point for now, I want to keep my curb as low as possible, but as I'm not sure one layer of bricks will be quite tall enough, what's the best way to add just a little height without going so far as to stack the bricks 2 high, which would be overkill?

Do I just pile the mud on really high? Or mortar on a slice of hardie board (all of this is under the membrane, I know)? The bricks are 2.375" high and I would want at least 1" of additional height on it before the membrane wraps it and then another .5" over the membrane. Can it just be mud or would that be too thick?

I had thought about sandwiching two bricks together on their sides but that would mean a wider curb, too.

06-02-2015, 10:36 AM
Schluter has a foam curb you can cut down to whatever suits you.

Or you could cut down a piece of kiln-dried 2x4.

You do need to keep your curb a minimum of 2" above your drain.

06-02-2015, 12:24 PM
If I am using a paintable membrane over my hardie board, what kind of thinset is best for installing my large porcelain? My previous project involved a vapor barrier behind the backer board, so this is foreign territory. I had read that if you use a waterproofing membrane on the surface of the backerboard, you may not want to use fortified/modified thinset because of vapor transmission issues, but it seems to me that modified thinset would be necessary for the large tile. So I'm looking for a bit of clarification there.

And can I use the same thinset to install my curb bricks on the slab?

06-03-2015, 02:50 PM
Bumpity bump...

Anyone say thumbs up for modified thinset over for using large porcelain on shower walls?

06-03-2015, 02:54 PM
I like Versabond. The white stuff is about 15 buck at homers.

06-03-2015, 02:57 PM
For my Kerdi waterproofing membrane (on drywall), I used Mapei Kerabond, which is an UNmodified thinset. My tiles were 12x35 and 12x24. Schluter's instructions clearly call this out so that made it easy. :)

I would read up on the manufacturer's installation procedures for your chosen waterproofing membrane and see what they say. You could call 'em, too.

If you're going with Hardibacker board, just keep in mind that it soaks up water like crazy and could dry things out. For folks applying thinset directly to it, wetting/wiping it down with a sponge a priori is recommended. You might mention the type of backerboard you intend to use with your waterproofing membrane. I'm not sure if a similar procedure is necessary.

06-04-2015, 07:58 AM
I did find on the installation page to use modified thinset after all. I guess I overlooked that previously. But now that I have to hold off until I figure out what to do about my non-draining linear drain (separate post), which was the next thing I needed to install, I'll be sitting tight for a bit. :bang:

06-15-2015, 04:32 PM
Quick question... Is quikrete all purpose sand too coarse for deck mud? I can't remember if that's what I used before or play sand.

06-15-2015, 04:54 PM
I used the all purpose sand, worked just fine.

06-15-2015, 05:49 PM
The mix of those bagged sand products varies rather dramatically from region to region, Allison, and we can only guess what you'll get. My experience is that it's probably too fine, but with big (small pea) pieces of stone that must be picked or sifted out.

06-15-2015, 07:26 PM
Cx, that's what I'm seeing. I don't remember it looking like that in the past. I think it is what I used in the past but I am not looking the looks of it now. I may switch to play sand...
Although... I wonder if the quikrete will suffice for the preslope only. I already have 6 bags at home. That's heavy stuff.

06-15-2015, 10:22 PM
You'll not be at all happy trying to form a pre-slope with the Quikrete if you're talking about the concrete mix. What's the number onna bag?

06-16-2015, 07:22 AM
I'm talking about their.brand of all purpose sand. No, I have Portland cement type I/II.

06-16-2015, 11:12 AM
So in addition to the sand, I have something else to throw out there.

I need just a bit more size out of my curb. Can I use a half inch of mortar on the top and sides of the bricks BEFORE I put my membrane on, and then do another half inch on top of the membrane? That will give me the size I need.

06-16-2015, 11:31 AM
You could, but I'd recommend you install the liner and put the entire 1" of mud on top of it. Likely take two lifts to get that thickness, but that's not really a problem.

My opinion; worth price charged.

06-16-2015, 11:38 AM
Thanks. And here is a diagram of how I am thinking of building that up, showing only to the mortar, not the tile.

06-16-2015, 02:42 PM
I don't have a problem with putting an inch on the top... just wanted to make sure my curb was high enough for the liner to be good and high over the curb, so that's why I wanted to add it under the membrane as well. If I don't do it under the membrane, the membrane will be lower than the finished floor where it meets the curb.

I'm trying to keep the curb as small as possible, but my calculations show that all of this SHOULD work, to my understanding. it puts the membrane of the curb more than 2" above the membrane at the drain... and the finished curb height at 2" higher than the finished floor at the drain. I know some people recommend more than than the minimum, but I was hoping to keep things low profile. I can increase that top layer by another .5" as well, unless that's overkill.

Look ok?

Or I could put a slice of hardibacker instead of mortar... UNDER the membrane...?

06-16-2015, 05:25 PM
Can't comment of the construction methods of your curb but regarding the hieght, your is very similar in relative height to mine.

I believe mine is about 5" tall and about 3/4" above the bed before adding the granite curb top.


06-16-2015, 06:31 PM
That's good to know. Well, if the method of raising the height is ok, and the measurements are ok, then hopefully I will be able to proceed tomorrow.

06-18-2015, 03:56 PM
Now back to the sand question.

As CX described, my quikrete brand of all purpose sand has some small pea sized bits in it. However, having six bags of the stuff already at home, I'm inclined to use it if it will work for the PRE-SLOPE. Then I'll head back for play sand for the top deck. (Yes, I'm using with Portland cement)

Should that be OK?

And if anyone wants to double-check me on my measurements, post #116, I'd be most appreciative. :)

Now, if only my back would heal... :crap:

06-18-2015, 04:22 PM
I'm not following your diagram. Can you label it as to what is what and point to it and stuff? :D

06-18-2015, 04:25 PM
Well, my photo editor is crashing every time I try to use the text tool right now... so the light gray block is brick, and the surrounding two layers of dark gray are mortar. The red line represents the liner and preslope. The blue line represents the top of the final mud bed. And I realize the blue outlines on my gray shapes may confuse things, but just ignore those.

06-18-2015, 04:35 PM
Ok, here!

06-18-2015, 04:40 PM

Okay, I think I have this right. I'm no expert in brick mortar (Type S, I assume or what??) so I dunno if slathering it on that thick is a good idea or not. I'd lean to it not being a good idea and would instead build up your curb with CBU. I think Durock comes in at 1/2" just like drywall.

06-18-2015, 04:47 PM
It's a half inch thick each layer. CX replied on the previous page about it and said he'd actually recommend the full inch on the top of the liner, but I'd like to keep the liner up higher, so that's why I split the difference.

I had actually also posted the question about whether I could put CBU on it to build it up and didn't get a response on that particular part of it. I had actually already cut some pieces just to play around with it...

06-18-2015, 05:03 PM
I believe that full inch he suggested was for the final deck mud.

That is different than the 'mortar' you are using for your brick curb...right?? :stupid2:

Perhaps you can find some larger pavers that might work in place of your brick?

06-18-2015, 05:35 PM
The full inch on top CX meant was the final deck mud atop the curb, yes. So the only difference here is that I have a half inch under the liner. I can also put the top mud on a little thicker than the half inch but my main question had been about it being ok to put it under the liner in addition.

And mortar, meaning fat mud for the curb.

I had not considered rethinking the construction method after CX said it would be ok... and was really looking for more feedback on height of preslope vs curb, etc.

06-18-2015, 11:02 PM
Let's be clear, guys.

The final deck mud for a traditional shower floor must be a minimum of 1 1/2 inches thick per ANSI standards. Has nothing to do with a curb.

The mud (fat mud or wall mud) on the curb an be as thin as a half inch. My recommendation of the one inch thickness was based upon the OP's requirement. I'd rather see a full inch over the expanded metal mesh over the liner than a half-inch under the liner and a half-inch over the liner, but either is acceptable. No mention was made of any deck mud on top of the curb.

So long as the liner slopes to drain, of course.

My opinion; worth price charged.

06-19-2015, 07:34 AM
Cx, you're right... I think things have gotten a little confused, but from a terminology standpoint. I said deck mud on the curb and that wasn't an accurate way to put it, but what I meant by it was that it would be the top layer over the liner. Fat mud is the plan for the curb. One and a half inches minimum is the plan for the top deck, which is a separate issue. So yes, I think we are clear on that, thank you.
My only point where I was seeking advice on the curb at this point was in size and relative proportion. That and the all purpose sand. :)

06-20-2015, 11:03 AM
I think I have answered my own questions in that I have bricks now that will be the right height all by themselves and will just screen out the larger pebbles from the sand as needed.

Now onward... we have a big stack of hardie backer for the walls. However,I want to bury in the top deck of mud. I'm seeing a lot of disagreement on this issue. Can the hardie be buried, and, if not, what can ?

Also, I will be applying redgard. Before or after the top mud deck?

06-20-2015, 11:18 AM
Neither Hardibacker nor any other Fiber/Cement board can technically be buried in the deck mud of a traditional shower receptor. It must be an actual CBU to do that. My personal experience with the Hardibacker tells me I wouldn't worry at all about it being embedded in final mud bed of a properly constructed receptor, but the industry standards and manufacturer say not to do that.

My opinion; worth price charged.

06-24-2015, 01:51 PM
Mud pre-slope is coming up soon, possibly. And with a shower floor that's about 5' x 6' I am wondering if anyone has any tips for doing my mud work in such a large space. The last one I did was considerably smaller.

I am planning on working in batches one area at a time, going from one corner to the next in sort of wedges extending out from the drain.

Do I need to be worried about one area drying out before doing the next, etc? Any tips appreciated. Thanks.

Oh, and yes, I changed my user name, but it's still me!

06-24-2015, 08:06 PM
Oh, and yes, I changed my user name, but it's still me!

Thought someone had hijacked your thread. :postitbg:

06-24-2015, 08:22 PM
I forget and am too lazy to read back but aren't you using a linear drain at one wall such that your mud pan is essentially a ramp? I didn't think you had multiple planes to shape.

But let's see: one to mix, one to pour, one to shape/screed. :D


alison still mad? LOL!

06-24-2015, 08:57 PM

Yes, linear drain, but not the fancy schmancy kind, so my preslope will go to a regular clamping drain assembly. Then top bed more like a ramp.

06-25-2015, 02:42 PM
I just wanted to check back in. Seems slow today. So here's an incentive. I'll make a thinset yard bunny for the poster with the best tips on how to work a large mud bed! :D

06-26-2015, 08:01 AM
Anyone? I just don't want to get humming along tomorrow and find out after the fact that I should have misted it with water or something. There will be a point when I will have to join the first mud I pack with the last mud I pack and I don't know how many hours that is going to take me. Plus, since I have to be inside the shower for most of the work, it's going to be challenging to not be the only thing the bonding things sticks to. If it's no big deal and there are no magic incantations to perform,I will just proceed and hope for the best!

06-26-2015, 11:36 AM
You don't mention how you're mixing up the mud, but if it's in a wheelbarrow, about all you can do is have everything on hand so that you can go from beginning to end without having to stop for anything. Hide your cell phone for a couple of hours to keep from being distracted.

I would probably mix as much as I could handle at one time so that you're stopping less often.

Going from one side to the other is a good idea, that's the way I do mine to keep it from getting too dry.

06-26-2015, 11:44 AM
CX likes to go with the 'bucket mixer' approach where he mixes up a 5-gallon bucket worth of mud. He prepares several of them in advance and then adds water when ready for the bucket. He often posts a pic of the bucket and the mixing auger/paddle he likes. Maybe he'll be along soon and post it for you.

I would strongly suggest you get at least one helper. I admire you going at it alone (at least it sounds like you'll be solitary) and so a big hearty :goodluck: to you!! :D

06-26-2015, 12:44 PM
Not all alone... I'm putting my husband in charge of mixing! Maybe. :D

We did it in a wheelbarrow before, but the multiple buckets sounds good. We won't be able to get the wheelbarrow into the bathroom anyway, due to a sharp turn at the bedroom door, so I was going to have him pass me buckets through the window.

07-13-2015, 01:23 PM
I'm fast forwarding here, since it's been a couple of weeks! I do believe it's ready for tile, though I will be taking a little time off first.

In the meantime, I want to finalize plans for tile layout. My originally preferred layout won't work because it would leave me needing really thin slices of tile for the bottom row. So I'm going to try to adjust things a bit - and that got me wondering what the thinnest usable slice generally is? I couldn't find the answer by googling. I don't have a cutter yet but will probably be getting a regular tile cutter, rather than going the route of a wet saw or anything like that. It's 12" x 24" porcelain running bond.

So here is where I am... and as promised... an exquisite mud bunny in honor of your help! :rofl:

07-13-2015, 04:21 PM
You technically want to avoid any cuts smaller than half a full tile, Alison. That's about all you'll find on the subject in the ANSI standards.

Lots of smaller cuts are used in the real world, but you really wanna avoid "skinnies" anywhere in your layout. Other than that it's up to the eye of the person writing the checks.

I'll copy that mud bunny to the yard bunny thread ( :)

My opinion; worth price charged.

07-14-2015, 07:57 AM
I prefer to limit my tile to 1/3 of the tile length (or width) in general but I've regularly used smaller section cut as accents.

For my master bath, the bottom row is 2/3" full size and the top tiles were about 1/3 of full size. The front of the shower is trimmed out with 4" (1/3 of tile width) accent cuts which worked well with the Schluter edge trim.

I've attached a couple of pre-grout pics which illustrate the use of the ratios. Of course, this reflect my personal preference for balance ratios; lots of other option out there. I recommend you do a layout drawing to get the look you want before you start setting tiles.

Nice work on the mud base! (and bunny :))

177877 177878

07-16-2015, 11:13 AM
Nice shower, pc!

Next question... Does anyone know where I can buy the caulk that matches fusion pro grout colors... Or even what it is called? Custom's website says they have matching caulk but don't actually seem to have the product on their website. HD carries the grout but not the caulk.
I had checked into Mapesil and have found that caulk locally, but with the price of Flexcolor CQ being so much higher than Fusion pro, I'd rather find the silicone caulk that matches Fusion Pro and go that route. Plan B being possibly to try to match a mapei color to the Fusion Pro.

07-16-2015, 01:10 PM

Color match is close but will vary based on how thick the sicon is applied. I believe you get the best match if you main the proper ratio; silicon depth/thickness = 1/2 X width of the silicon line.

FYI: Thicker is not better with silicon If you go thicker, the silicon will shrink and pull away on the sides.

07-16-2015, 01:59 PM
Thanks for the lead. Any idea on cost per? I can get mapesil for about $14-15 ea.
And do you know if that coverage chart on their website is showing linear feet?

Tiger Mountain Tile Inc
07-16-2015, 05:31 PM
Colorite is out of Oklahoma and the shipping for you won't be as bad as it is for me. Their stuff is a little more expensive for me than if I just buy the manufacturer's product but you can get a satin finish with Colorite.

You can order this product ( from Home Depot but they won't stock it. Also it won't come in every color. If you can't find the right color then Colorite is definitely the way to go. :)

07-16-2015, 07:34 PM
They have a price sheet on their web page; shipping will add $8-$12.

Recommend buying the smoothing tool and mist stray from ColoRite; makes a huge difference in the quality. KG posted this on another thread today, right on point.

If you go out of your way to discharge just a little bit more caulk then needed, then spray the joint with denatured alcohol and use a smoothing tool (like you get at ColorRite or the hardware store), the joint will come very clean and form a neat bead in just a single cleaning pass or two

Here is a before and after from one of my projects. I was a little too generous with the silicon but you get the idea.

177954 177955

07-16-2015, 08:44 PM
Jim... Yep, that's the caulk I was looking for and couldn't find it on hd's website.

EDIT: Wait! I found it! Not in the color I was leaning toward, however...

Actually, it looks like almost a completely different color palette.

09-01-2015, 12:06 PM
I just had to share my progress! I am so excited I could just burst. :clap2:

Everything has gone really well. I just finished installing the tub filler, and some pros just dropped by to measure for the enclosure. It's not perfect, but I'm pleased.

Next, I'll be demolishing the old shower, which has stayed intact just to the left of the new shower... and opening the wall between it and the closet which is now sealed off due to the new shower being built over its door.

Then I'll tile the bathroom floor, which, as it turned out, was about 1/2" off level in places, so I did use some SLC... which isn't a magical cure-all as some would have you believe, but it did ok with some encouragement. I'm sure as I embark on these final big steps, I'll have more to discuss! :neesie:

09-01-2015, 04:56 PM
Some perspective...

09-01-2015, 06:24 PM
Pretty slick, Alison!

Now stretch one arm straight up toward the ceiling, bend it at the elbow, and pat yourself on the back. :D

Tiger Mountain Tile Inc
09-01-2015, 08:21 PM
Looks like a palace. :tup1:

09-02-2015, 07:22 AM
Thanks, guys!

I do have a question. Is there any rule of thumb about how high the glass should go? I need it taller than standard 72" and had a glass company quote me 80". That takes it to the middle of the top bullnose. But I wondered if I should do just a wee bit shorter than that to avoid it looking like an aquarium. Or would it look ok that high?


09-02-2015, 11:33 AM
As long as it's over the user's head, that'll keep water in. :)

Tiger Mountain Tile Inc
09-02-2015, 08:28 PM
Consult the glass people. My glass guy usually doesn't like to go above 78" with the 3/8" glass. Somewhere in the 72-78 inch range is the norm from what I understand.

09-05-2015, 11:19 AM
At this point I'm thinking 76 inches would look good.

Now, I've done the demo on the old shower walls and have the floor left. It's a traditional mud and liner pan. The top layer of mud under some of the tiles I've popped out looked wet and really dark, like maybe moldy. Should I bust that entire layer out?

Either way, I'll have several inches to fill in to raise the old shower floor to the level of the adjacent slab. What's the best concrete to do this with? I'll be tiling over it.

Lastly, the drain poor for an upstairs tub and toilet run down the wall next to the shower. Would I need the old shower drain to be capped off but still accessible to service this drain line? This whole branch of the drain has been very slow lately.

09-05-2015, 01:14 PM
Some of us are confused, Alison. Are you starting on another shower about which we know nothing?

...the drain poor for an upstairs tub and toilet run down the wall next to the shower.By "drain poor" do you perhaps mean a vertical DWV line that goes at the bottom to your main drain and at the top to a vent through the roof? Commonly called a drain "stack" and frequently larger than your other internal drain lines?

'Till we get more information, I'll say you should certainly find out why your drain is slow and correct that situation before moving on to other drain work.

09-05-2015, 02:05 PM
That word "poor" was an accidental inclusion due to my tablet making up words for me... just meant drain, but nonetheless you understood me correctly. And yes, before doing anything to cap that old shower drain, I want to make sure all drainage in that upstairs area is up to par, so we understand each other on that point as well... I think.

As to the other shower... my new shower that I just finished is in the old bath tub location. We kept our old shower in service until the new one was operational. So now I am doing the demo on it and that space will become an expansion to an adjacent closet. But that discussion was eleven pages ago. ;)

So I'm wanting to get the demo done on the old shower before having the glass enclosure put in and laying the new tile floor in. I'll save finish work on the old shower/closet for later, but I just wanted to get the demo done.

09-05-2015, 02:25 PM
per the above, here is a picture to show new versus old...

And another to show the floor of the old shower. Just out of view at the top is an elbow where that smaller vent pipe meets the large one.

09-05-2015, 03:23 PM
Understand. I had not read back far enough to see all that's going on.

But I still don't see why you are raising the floor. Is that because you just don't want a step down into your shower, or is there another purpose? Would I need the old shower drain to be capped off but still accessible to service this drain line? And I'm still not finding enough information to answer that question. If it's in here, please point it out to the old, slow ones amongst us. :)

09-05-2015, 03:34 PM
I need to raise that old shower floor so that it is level with the rest of my floor so that I don't have to step down into the closet. That old shower is becoming part of a closet, and the old shower door will be the closet door.

And my question about leaving the old shower drain accessible is just because I thought perhaps it might be easier to have a ground floor access point for snaking a drain in the future, should we ever need to do that. Then again, I've never had to actually call on roto rooter, so I wouldn't know.

09-05-2015, 04:04 PM
OK, thought you were building another shower in there.

Leaving access to that drain stack certainly wouldn't hurt if you can put a clean-out fitting in there.

Raising the floor can be done either by pouring concrete in the hole or packing it with deck mud if you plan to tile the whole floor. Chances are you'll have an issue with the tile installation in either event and use of a good crack isolation membrane would be indicated. That may not be enough without honoring the joints, but in that particular application I think you might get away without doing so. Operative word being might. See my warranty information below.

My opinion; worth price charged.

09-05-2015, 04:17 PM
Ah, so at the joints where new concrete meets old, I'm likely to have cracking? Good to think about.

Being a closet, I was going to transition to a smaller and cheaper tile size, right at that threshold and can try to make sure I put a joint with caulk at both places where new meets old. Would that be helpful?

09-05-2015, 04:31 PM
Very nice work Allison. That about the best tub shower setup I've seen!

09-06-2015, 11:25 AM

10-19-2015, 12:46 PM
Well, my work in here is almost done. I got the bathroom floor laid out in a herringbone pattern and grouted last week and got some of the caulk done around the perimeter this weekend. (Then I ran out!) Just a bit of work in the old shower-turned-closet left to do. I'll be back after the glass enclosure is done but just wanted to share my results! Thanks to all!

10-19-2015, 12:55 PM
Very nice, Alison. :clap2:

10-20-2015, 12:51 PM
Thank you!

10-23-2015, 06:17 AM
Looks great Alison! Very unique!

04-20-2016, 08:36 AM
It occurred to me that I never posted my final, final after pics of the finished job. We used a plastic shower curtain for months and finally got the glass installed last month. So now it's looking great and it's a nice, comfy shower to use. And the kids love the "relaxing tub." :yeah: Thanks again for everyone's help!