Best bet is to do a mud pan. The reason I say that is that with the Schluter shower trays, the drain must be perfectly centered. being that this is a renovation, and you may have to go with existing conditions, (the drain being wherever it lands) a mud pan would grant you that versatility, and still allow you to use the Kerdi drain and membrane.

Thanks Bill for your expertise!

I apologize for what are probably stupid questions, but I assume you think our best approach would be to (q. 1) follow the Schluter instructions for Kerdi-Drain, in which they explain embedding the kerdi membrane "into" mortar?

(Q. 2 )And that this takes the place of some other type of pan, such as lead, poly, rubber?

(Q. 3 and 4) And that the "mud" (which is mortar--modified? or unmodified? or something else?) plus kerdi membrane has superior waterproofing and better longevity than using one of those other types of pans?

Notice I tried to number my questions so you can just say "1. Yes" (or no) etc! To extent possible.

I can't thank you (and Mongo) ENOUGH for all the fantastic advice and info you provide!! Even though we're having others do the job (obviously---know so little) I want to be as educated as possible about how it should be done. God bless you!

Lainie

(Q. 2 )And that this takes the place of some other type of pan, such as lead, poly, rubber?

Yes

(Q. 3 and 4) And that the "mud" (which is mortar--modified? or unmodified? or something else?) plus kerdi membrane has superior waterproofing and better longevity than using one of those other types of pans?

The mud is what's known as "dry pack" or "deck mud". It's a mixture of sharp masons sand and portland cement mixed about 4:1 sand to cement, and then mixed damp. When mixed properly, it looks like damp sand.

As for the second half of your question, without a doubt. The thing about the Kerdi system is that it's a topical system, whereas the others all go underneath the mud. With the Kerdi, the ONLY things that get wet are the tile, grout, and thinset, which makes it easy to dry out extremely quickly, especially when coupled with a good vent fan, which gives mold and mildew virtually no chance to get started.

I used the Schluter tray on my second floor bathroom. As Bill stated, you will need to make sure your drain is centered, or at least falls within an acceptable area if you have to trim the tray a little. In my shower I used the 48 x 48 tray, and my shower ended up being only 45 inches wide. That gave me a little over an inch each direction I could be off and make it up when trimming the tray. The only other tricky issue is making sure that the drain gets firmly cemented into the trap which can be a little tricky depending on your conditions. If your trap is not securely attached to the framing, it may give when you push the drain stem down into it. Thin setting the 2 half-circles under the drain flange is not difficult. Then the last thing to cover is making sure you get exact measurements for the rest of the tray if you have to trim it since your center point is already fixed.

The Schluter pan is a great DIY option if you don't want to tackle a mud pan, but as Bill said, the mud pan is your best bet if you are hiring it out or if you feel comfortable doing it.

Joe

Lainie,

Somewhere buried in the archives is a Kerdi Shower thread, I think I titled it "Kerdi Shower with Niche".

It has a quite a few photos of a Kerdi install, about halfway through it addresses the drain and deck mud installation.

The reason I mention it is that shower was a second floor installation, and I had to move the existing drain over a bit. I did not have access to the plumbing from below. What I did was I cut a hole in the existing subfloor, rearranged the drain location, then added another layer of 3/4" CDX ply over the existing subfloor that I had just butchered to create a new subfloor.

That shower didn't lend itself to a Kerdi Tray, as it was something like 5' by 8', so I did deck mud.

What I will say is that you'll have one decent shot at setting the drain from above if setting it in deck mud.

What you have to do is dry fit everything so that the flange on the Kerdi tray is sitting the appropriate height above the subfloor, with it also being level. Then remove the dry set drain.

THEN you start doing the deck mud. When it's time to set the drain, you glue everything up and all at once glue the Kerdi drain to the trap assembly below while also setting the flange of the Kerdi drain into a ring of deck mud, getting it perfectly level.

It's not terribly difficult IF you dry assemble sat level. Remember, the Kerdi Drain is about the size of a frisbee, so you need it level as can be.

In your case, if you can relocate the drain to center, then patch the subfloor with blocking (if required) and a second layer of CDX, you can then use a Kerdi Tray since the drain stub out will be centered.

Hope that makes sense. My situation was somewhat easy, as I didn't have to move the drain all that much.

Mongo

I was wrong, the thread was titled "Kerdi Shower". Shows you how much I pay attention to my own threads.

The post that starts the segment on the drain is titled "Kerdi 22", after the thread loads pull the scroll bar about 1/3 the way down the screen and that should get you close.

I didn't address relocating the drain that much, but it shows the old drain cut out, a new section of clean CDX installed, and then proceeds with the deck mud and drain installation.

It may not be much help, but, hey...you'z gets what you'z pays for. ;)

Will post for food...

Mongo

Will post for food...

not me!! I may be easy, but I ain't cheap!! :-)

Thanks so much Bill, Joe and Mongo!

This is definitely NOT being done by me nor by DH.

Funny but after I posted last night, I started to review that old fantastic post from Mongo....but then 4 a.m. hit...I even got to the exact spot that Mongo referred to.

Seriously though, a few more questions:

1. The shower interior will end up about 46 inches by 36 inches, so if we used the Schluter tray it would be cut down from their 48 by 48. Thus, some flexibility....?

The existing drain location seems very close to center of the current shower--which is an ugly gray prefab unit--I will flip for joy when that is demolished!

Q. 1: Does that additional input change anyone's view on the practicality/feasibility of using a Schluter tray?

(It does sound like a "mud job" would be less stressful/ more realistic).

Q.2 for Mongo....you wrote "What you have to do is dry fit everything so that the flange on the Kerdi TRAY is sitting the appropriate height...."

Did you mean DRAIN, not TRAY in that statement? (Cause I thought you were assuming that using the shower TRAY was probably not going to work....?)

Q 3. for Mongo..."It's not terribly difficult if you dry assemble sat level. What is "sat"?

Q. 4 for Mongo..."What I will say is that you'll have ONE DECENT SHOT at setting the drain from above....:
Do you mean "it's a decent/good/fairly easy shot...OR do you mean, "You've ONLY got ONE shot so you (or tile pro) better not screw it up!" ?

Q 5. If you'll work for food, why not just work all the way in the Western part of the state? (I know...the traffic is HORRENDOUS!!). But a person can dream, can't she?

We had such a wonderful carpenter finishing our basement a few years ago that I provided him with 2 meals a day...oh yeh, we paid him too!

Thanks again, all!

Lainie

1) No it's fairly easy to cut down a tray, you'll be taking 1" off two opposing sides and 6" off the other two opposing sides. With a pitch of 1/4" per foot, you'll have less than 1/8" differential along the top edges around the perimeter of the tray. You still set the bottom course of tile level and the differential in the wall/floor joint will be somewhat invisible.

2) Correct, should have been "drain" not "tray".

3) Should read "It's not terribly difficult if your dry assembly is level."

4) Well, you're simultaneously gluing up PVC (or ABS) while trying to set the flange perfectly level in a ring of mud (if a deck mud base). You have a few seconds until the glue sets, then it is what it is. It's not difficult, but it's a one-shot try.

If using a Kerdi tray it's a bit easier as the tray is level. Set the flange on the tray and viola, you're there. You just want the plumbing beneath the drain to fit properly so that the plumbing doesn't try to "pop" the flange off the tray, ie, no upward force.

So...yeah...don't screw it up! ;)

5)I was just out in Sherman. Not sure where you are.

6) I'm cheap, easy, and HUNGRY! Malnourishment is what's causing all these typos! That's my story and I'm sticking with it.

Sorry, Newbie question. I'll be gutting my old 50's bungalow main bathroom that has an old shower/tub combo in it and redoing it with amongst other things a new shower stall. From the forgoing threads, am I right that for the new shower pan the appropriate options would be either move the drain to the center of the footprint of the new shower stall and install a Schluter shower pan with Kerdi wrap for the rest of the shower or leave the drain where it is and use a mud deck and then use a Kerdi wrap?

Thanks,
H

H,

If you have an existing tub and would like to convert that same space to a walk-in shower...and NOT move the drain...and NOT do deck mud...

Schluter does offer a preformed tray the size of a typical tub footprint. It's about 32" by 60". One version has the drain centered in the tray, the other version has the drain about 10" from the end to coincide with the drain location for a typical tub.

Mongo

Mongo,

Thanks for the replies and help. I blame my typos on dark chocolate! Live in small, bucolic Easton, just north of Bridgeport.
I don't know where Sherman is; but it might even be smaller than Easton which "ain't easy." I realize you're quite far if in Eastern part of state.

Lainie

Sherman is a little NW of Danbury.

I was down in Atlanta for a couple of weeks, I drove past you today on my way home from the airport (LGA). Head up I95, I'm off of exit 64.

You're closer than I thought. :-) I've got cousins in Guilford right off 59, and three sisters in Branford right off 57, including the one in the business. :-)

Gosh, starving Mongo...had I only known I could have handed you a bag of potatoe chips while you sat in a traffic jam on I 95!

(Actually I am very close to Route 15/Merritt Parkway, which is a whopping 10 minutes away from I 95; with traffic just as bad during rush hour. But when it's not rush hour, they do construction. Good times.)

Cheers,

Lainie

Always loved the parkway. It was such a good place to get all my phone calls done, being I didn't have to watch where I was going......AT AN IDLE!! :-) I used to live just off of it.... literally-- I lived in a house right at the end of the southbound exit ramp on Wheelers Farms Road in Milford, going back about 20 years ago!! :-) It was a terrific place to live-- Some people have to worry about vibration from passing trains. me, I had to worry about the shaking from CH-53 Helicoptors flying over from across the river at Sikorski while training pilots!! (for those who don't know, those are the helos that you see carrying TANKS)

Thanks Bill and Mongo!

Cheers,
H

When the Merritt is moving I love it. A much prettier drive. The downside is when it's at a standstill, there's no way to escape!

About once every 5-6 months I see an 18 wheeler accordion its trailer by getting stuck under an overpass. More common on the Hutch than the Merritt.

Why is it called rush hour when everything moves so slowly?

"All I know is a plumber told me that a "poly pan" will last 10 to 15 years....and that is unacceptably short!" I agree. What are the lifespans of the fabric and the drain? 10-15 years as well?