Failure of a large mud shower pan.

[Paul Lepkowski]

#20 - #23 looking into the shower showing old joists recessed below adjacent tile floor
These joists have been cut away since they were very poorly cut and were moldy.

 

[Jadnashua]

A lead pan in an by itself, over time can tend to get cracks in it...plus, in a shower, the liner, whether it is on the top of the pan (surface membrane) or buried in it MUST be sloped to the drain. The LINER is the waterproofing layer, and the tile is considered a decorative, wear surface that is much easier to clean and maintain. Do NOT put your liner flat on the floor, and I would NOT use a lead one (or copper for that matter). Whatever you do, if your liner is flat without slope, you will end up with wet tile and grout, and it will be hard to keep mold from forming. THey tend to start to smell like a swamp after awhile, too. If you ever had to tear out a shower where the liner was flat on the floor, you might not want to eat for a week - really nasty.

Most states abide by some sort of plumbing code, and all of the national ones that the states base theirs off of (some adopt them in their entirety, some have amendments) have the shower pan defined - usually to define the slope and the height of the waterproofing above the curb which gets messy when trying to do a barrier free install. There may not be any enforcers in your area or inspections, but it is still supposed to be made to meet the code.

 

[Sponsor]

 

[Paul Lepkowski]

Hi guys,

I hope the above pictures give you an idea of what I’m dealing with. Eight years ago I paid this bozo $23,000 to reverse the layout of a bedroom / walk in closet / bathroom wing. The job looked very good when he finished. The wing is 22’ x 35’ so the price wasn’t too bad.
The mold in the crawl space was discovered when we were installing a giant sit down bath tub in the adjacent bathroom for my wife who has balance issues after a stroke. We’re living on our savings plus SS so I can’t afford any more mistakes.

The local masonry and tiling contractors seem to act mostly like used car salesmen and I don’t trust them. The guy who screwed up the original membrane installation is still around, but he has bankrupted three corporations since then and won’t stand behind the failed job. I am trying to do the job myself with the help of a good friend who is a refrigeration technician and used to be a plumber. At 74 years old I am no longer physically able to sling mud myself.

RedShoe – In the last three weeks the jack posts in the photos have been replaced with cement filled lally columns. The numbskull who did it took the pressure off the jack posts before insert the new, somewhat too short, lally columns so the whole thing sagged. I got it jacked back up and shimmed with steel plates. It’s strong now. Those transverse beams under the joists are 4” x 12” laminates.

The moldy joists are gone and will be replaced with new ones on 10 inch centers. Six joists for 60 inches width. I have to determine the height of the new joists by the flooring method – membrane over mud vs. membrane over subfloor vs. cast solid surface slab. That’s why I’m writing this. I doubt that I’ll ever sell this house, we’ll probably die here.

These yuppies up here think that Hillshire Farms makes good kielbasa. We have to drive 90 miles south to Greenpoint to find the Polish butchers who make good kielbasa. Out there in Minnesota the sauerbraten, sauerkraut, spaetzle and coffee must be really good considering the number of Lutheran farmers living out on the prarie.

Eurob – This mud bed definitely did fail due to a spliced membrane installed by a numbskull. I planned on sloping it across the narrow dimension, the 60” direction, which would give a drop of 1 1/4”. The only SS wire mesh I can find is the rectangular type. I would like to use the expanded diamond pattern, but that only seems to be available in galvanized steel. Do you know of any place that sells the expanded diamond in SS?

What are you referring to when you say connecting the pipes in “wired way”? I don’t recall mentioning the plumbing involved. As you can see in the pictures, the original installation used a Grohe thermostatic mixer feed one Speakman shower head, one hand shower and three Grohe body sprays through three volume control valves. I plan on leaving it as originally installed. I might add a rain shower head through the ceiling if I rip the tiled ceiling out.

The ceiling was tiled over green board which should not have been done.

Comments please.

Paul in Fishkill Plains

 

[Paul Lepkowski]

Hi Jim,

I am not seriously considering a lead or copper pan. I just mentioned those to prove how old I am.

We do have a state code here but it is lightly enforced. Good thing too, because the original job eight years ago had a level entry suitable for a wheel chair which was not at the time permitted under the state code. I don't know if it is legal today and I don't really care. If a particular buyer doesn't want the house with the level entry shower my estate can find another buyer.

The original pan did indeed have a slope in the membrane. The first layer of mud, below the membrane, varied from 1.75" down to .75". It was a center drain so the distance to the end was 4' which provided the 1" total pitch. That layer was covered with a membrane which was spliced with an overlap in the middle. That splice is what failed. That membrane was then covered with 1" of mud, then with thinset, and finally with tile.

My desire to slope the new pan in one direction across the 60" dimension will result in a total pitch of 1.25".

Thanks for your comment.

Paul in Fishkill Plains NY

 

[Eurob]

I am not sure how to place your shower 60 '' x 107'' .

Could you show me a front view picture ? I think you can have the bench at the deep end , linear drain in front of it and full access front the front with the slope towards the end of the shower , which will increase the chance of water control for a no-curb shower .

I think you will be fine with the expanded galvanized , but I've seen the rectangular SS wire mesh installed the same way -- flat on the felt -- .

The mud didn't fail , the liner did . Not the same thing .

 

[Paul Lepkowski]

Hi guys,

There seems to be some confusion because this thing is not symmetrical. The shower heads were not on the centerline. Here are two pdfs showing the existing and proposed plans. I have removed extraneous details from these drawings. If anyone wants to see more detailed drawings just ask.

Paul in Fishkill Plains

 

[Eurob]

Hey Paul,

I will propose something like this . The linear drain can go from wall to wall .

The advantages are -- you are coming to an area where the sloping is not pronounced , you can have a bench while showering , you don't need an increased slope by cutting the distance with the bench , linear drain easier to clean and maintain etc. -- .

 

[Jadnashua]

If you go with a surface membrane, it is primarily the strength of the metal you use that becomes important, not the material (galvanized or SS) since it should never get wet again once the stuff cures. To gain maximum strength from the material, ideally, it should be in the middle of the mudbed lift.

Depending on the manufacturer you choose, they may have more stringent minimum thickness required in a mudbed verses the general industry standards. For example, Laticrete wants theirs to be a minimum of 2" thick and, they call it a fortified product. Industry allows it to be thinner. When it comes to the product you choose, using it outside their recommendations might, certainly not definitely, have issues. It would depend on if all of the possible bad things aligned, then you might really have preferred to follow the manufacturer's instructions.

It is possible to reliably seam any waterproofing membrane, but it must be done with care. I certainly would not want my metal, especially lath, directly on top of it!

 

[Paul Lepkowski]

Hi Eurob,

Why did you turn the drain 90°? I had it running east-west. You made it north-south. If you were worried about keeping the spray away from the entrance door that is not a problem. The old installation with the center drain worked for 9 years. The placement of the shower heads never let any significant amount of water get near the doorway in the west end. The only time that end of the floor got wet was when we mopped it and then rinsed it with the hand shower.

I don't want to install a fixed bench because it will make future maneuvering with a wheel chair more difficult, and both my wife and I currently need a little assistance getting up from a chair so we use one with arms. We had a nice, sturdy, rustproof, cast aluminum chair in there. I used it more than my wife. She can stand but I can't due to a bad back.

If I fabricated a 30" bench as you show then the remaining east-west length would be 77" which would require a total pitch of about 1 5/8". The 60" north-south distance only requires a total pitch of 1 1/4". If the total pitch increases by 3/8" the bottom of the sloped mud layer has to be lower which means the joists have to be thinner by 3/8" and proportionally weaker.

Paul in Fishkill Plains, NY

 

[Paul Lepkowski]

Hi Jim,

I'm confused. Why would I want to put metal lath on top of a membrane?

The sandwich stack order I proposed is either
a) joists, plywood, roof felt, metal lath and sloped mud, thinset, membrane, second mud, thinset, tile.
or
b) joists, plywood, roof felt, sloped foam preform, thinset, tile.
or
c) joists, plywood, roof felt, cast sloped solid surface slab (corian).

I would prefer (b), but they don't make preforms larger than 55" x 55" with a linear drain. They suggest using two 55" x 55" preforms side by side and filling the vacant stip on the north with mud to reach 60". That would create two "cold" joints, one between the 5" x 60" mud strip and the north edge of the preform, and the other between the preforms. I'm not too sure about the rigidity of the cold joints under tile. If they flex there goes the tile.

Is there any way I can fabricate a sloped layer out of anything other than mud?

Why do they say you can install tile bedded in thinset directly over the membrane which is bedded in thinset directly over the foam preform layer, but you must have a second thick mud layer over the membrane when it is over a sloped mud layer????

Paul in Fishkill Plains NY

 

[Vegas_sparky]

Depends what you are calling a membrane.

A liner material will be between two mud layers(preslope/mudbed). These liners are typically a very smooth material, which would make bonding anything to them difficult. The mudbed on top of the liner protects it, and should have enough mass to be stable, while providing an adequate surface to install/bond tile over. Joist, plywood, felt, lathe, preslope, liner, mudbed, thinset, tile, grout.

A waterproof surface membrane(ie:Kerdi) has additional material to facilitate mechanical bonding to it. This can be installed directly to the single sloped mudbed, and tile installed directly to it. Joist, plywood, felt, lathe, sloped mudbed, thinset, membrane, thinset, tile, grout.

Those are generalizations, and I'm just an amateur. The pros will correct and clarify my blabber.

Also, I'd rather not have any of your kielbasa. I mean really, we've just met. LOL

 

[ShowerDude]

Paul,

You need to first pick a method to move fwd.

Even here on this site you are going to get advice from at least 3 angles and methods. 1 of which comes from a retired salesman from New hampshire that..... I REPEAT does not build showers for a living. Or build anything.


IMO Roberto would be your better bet here based on experience/product knowledge/ and hands on lifetime of building.( I choose to get my advice from hands on builders)



FWD:

I am having a hard time discerning your pictures, they are very small and hard to see when blown up!
I do not like your framing. Cut Joists and crooked jack post/beams.( in itself a large drawn out converstaion.)


Still Moving FWD:

If you intend to simply move fwd with this framing and layout for your linear drain ( the long 103" way)

Prepare for an EXPENSIVE $ 1K + custom drain. Robertos method of re arranging layout will save you $ and help with pitch/mud bed. But I understand you have handicap concerns with that layout.

Your method the long way, if im seeing your pics properly will be a challenge to get drain/trap/riser placed directly above your sil plate (if you are trying to push it all the way to the wall you may need to force ot more to the inside of the shower and force a multi pitched pan more to the ctr. ( again cant see direction in your pics. )


Still Moving fwd?

I would suggest some better support below. I would at least sister some 3/4 ply rips or 2x6 to your joist and bear on the sil plate and span to a better Support/post/beam situation. Then I would further cross block at minimum.( Whats done is done. Shouldnt have had knucklehead cut your joist !.)

The confusion you are really facing is your Mud pan/drain and how that works together........... You need to make some hard choices here. Start with choosing tile, a drain, and then a waterproofing system to go with it.

After you upgrade framing and layer that with 3/4 Exp 1 plywood and set your drain outlet/trap/location ( specified by your drain MFG).

You can then look at building what we call A "Thinbed" shower. A typical type of "Thinbed" shower. Every drain is different and requires a different approach.

Start here:

Pic your tile, then your drain, then your membrane. These choices will dictate how we can help you put it all together.

Nothing CHEAP and fast about this buildout.

 

[Eurob]

Hey Paul , I did put the linear drain at a 90 degree from your proposed plan , for the many advantages described in my previous post .

The landing zone -- 1% slope -- and the shower zone 2% - would give you roughly 1 1/8 to 1 1/4 , so it wouldn't be that bad .

The linear drain can also be placed 12'' in front of the bench , so the slope height is further reduced .

I mentioned to you few options -- angles -- to make sure you have them before you commit . Far from '' imposing '' anything on you and with such a distant participation , it will hardly be possible to see all the details affecting your build .

You should also consider others advices -- RSCB , John to name few -- , they are well rounded in building efficient and long lasting showers .

The bench -- designed per your needs -- and the walls can also accommodate support bars or any device helping for health related problems .

 

[Jadnashua]

A mudbed will be stronger if you use metal. It will work best if it is in the middle of the lift, i.e., with mortar on top and below it. When using a conventional clamping drain shower, you wouldn't really want to put the reinforcement on the liner, especially if it was metal lath - that stuff has some really nasty sharp edges. Buried in the mortar mix, no problem. If you're using a surface membrane, nothing beneath that membrane should ever get wet again, so corrosion on the metal reinforcement isn't really a worry. On a conventional shower, if you used some in the setting bed, you would want something that could stand repeated wetting.

 

[Jadnashua]

Even here on this site you are going to get advice from at least 3 angles and methods. 1 of which comes from a retired salesman from New hampshire that..... I REPEAT does not build showers for a living. Or build anything.

BTW, I retired from designing military missile control systems operational requirements...I advocate products I know work. Calling me a salesman implies I get paid for it. What may work well for a DIY'er verses in a commercial situation may not always be the same when there will be multiple contractors on site and you don't have control over the whole endeavor.

TCNA says 70-80% of the tiled showers built have at least one defect in them that affects performance. Building them for a living is no guarantee they are built right. Understanding how they should be built is important. The mechanical skills to get it right the first time comes with actually building them (and I've done a few, but never got paid for it, thus, not a professional...doesn't mean I don't know a good one from a bad one!). Understanding the different approved methods gives you some insight on what works and why. The goal is a shower build procedure that would work for anyone, anywhere and that is what the TCNA guidelines provide. Since each one is essentially custom, deviating from the standard may or may not bite you. A huge amount of research money went into developing those standards by both the manufacturers and the TCNA itself. Ignore their guidelines at your own peril.

 

[ShowerDude]

an

BTW, I retired from designing military missile control systems operational requirements...I advocate products I know work. Calling me a salesman implies I get paid for it.

Since each one is essentially custom, deviating from the standard may or may not bite you. A huge amount of research money went into developing those standards by both the manufacturers and the TCNA itself. Ignore their guidelines at your own peril.

Employment designing within the engineering field, earns you squat in my eyes. It does give me great insight into your ideals and rhetorical way of thinking. It also further proves the basic point you are not nor have you ever been a builder. You, simply not qualified to comment on products youve never installed, nor methods you have no experience employing.

Engineering missile buttons? A totally different skillset, im sure you are well versed in spring tensions and such, still A Far cry from a tile or construction professional with 20 years of hands on product use and a lifetime of closely watching the tile industry change such as John, or Roberto.

It is indeed the fact that you push booksmarts and research again and again with no actual experience other than a paid seminar or 3. This is the point at hand for readers, specifically casual DIY readers.


I am sorry i slandered you with the term Salesmen..Maybe "online promotional lobbyist" better fits. LOL.

XOXO- Redshoe


I have 10$ on this last question going unanswered, unproven. Any takers???

Again I ask, can you show us all right here your pre-paid receipts for admission to your recent sponsored seminars?

 

[Jadnashua]

You have no idea what I do in my time away from work, or the scope of what my employment history was.

 

[Eurob]

Who cares ? You have no proper training and hands on experience with tile and stone industry reality .

How many modified mortars you know work with the sheet membranes -- water and vapor proof -- ?

 

[Paul Lepkowski]

Hey, a cat fight!!!! Good, I'm a Polack, I like cat fights! I sense that this one has been going on for a while here in this forum. Now, where's that popcorn.....

Ya know, some of us have worked at one job for a long time, others have moved around a lot. I grew up on a dairy farm in Walton, NY, milking 95 Holsteins morning and night. Then in 1947 I went to Tokyo for 15 months where dad was reopening the far east division of United States Lines using 118 freighters to serve 1142 island destinations. After that I went back to the farm and helped build 4 barns, 3 houses, and milked a lot of cows. Then I played guitar professionally in the 1950s working up to WABC New York and a Capital records recording contract. I was pretty good. Then I spent 7 years at Cornell, MIT, Harvard and Columbia earning some degrees in useless stuff like Physics. Then I worked at designing radio stations and recording studios. I made some really good recordings of the Philadelphia Orchestra. I finally found a steady job in Avionics Engineering at Pan Am and wound up as Vice President of Engineering. After they went broke because the war department couldn't pay for the Kuwait war transportation I rebuilt tug boats in Port Bolivar, TX.

Now I'm retired, working on my eighth decade, in Fishkill Plains. In 2005 I hired a professional mason and tile setter to build a humdinger of a bathroom. It looked great, but it didn't last because the pro with the business name on three trucks was a schmuck and the membrane leaked. So I have to get it fixed, but the present day pros, all of whom claim 30 years experience but weren't in business in 2005, each have different ideas about what I should do, and each of them thinks that only he is right.

So, I came here confused. I asked, "Now what do I do … a new mud floor … a solid molded composite insert … or a membrane over a tapered support?" Now, I don't want you guys to stop the cat fight, I like it, and I fully expect you to start aiming barbs at me now that I have given you more ammunition about being a Polack dairy farmer, but I would like to end my confusion because I have to get this shower fixed sometime this decade.

1. The solid molded composite insert would be an oven cured plastic like DuPont Corian. The only difficulty would be dropping it in place on a layer of thinset over a plywood subfloor. It would outlast my grandchildren. The problem is that it will take 6 weeks to get, I will have to drive to Rochester with a trailer behind my Suburban to get it, it will weight about 600#, and it will cost about $2800.

2. The mud floor would be a sandwich of many layers, plywood, 30# roofing felt, tapered layer of floor mud (4 sand / 1 Portland / very little water), thinset layer, then a membrane. Then the confusion starts. Some say a second layer of 1 1/2" of mud is needed before setting tiles in thinset, others say you can then set tiles in thinset directly over the membrane. Is the second layer of mud really needed with modern fuzzy membranes which thinset can bond to? How important is the skill level of the mason who places the mud because I don't think much of the guys who've looked at the job?

3. All the membrane manufacturers say you can apply the membrane over a plastic foam tapered preform, but they only make the preform in sizes up to 60" x 60" so this was not an option. Yesterday I found that USG makes custom size sloped foam preforms which key together smaller pieces. So this now becomes an option. I have asked them for prices. This would be layers of plywood, 30# roofing felt, thinset, the foam preform, thinset, membrane, thinset and tile. This seems to be the simplest way to do it, but some of you don't think it is very permanent. How permanent is it?

Like I asked originally, what do I do? Help!

Paul Lepkowski in Fishkill Plains, NY

 

[Vegas_sparky]

If I were you, because elevations need to be controlled, I'd go with a sloped mudbed, with a surface membrane applied to it. A tiled shower floor is much more attractive than a plastic/fiberglass shower pan, in my opinion. The foam will need custom mudwork to complete, so you'd probably lose as for saving time/money with that route. (On edit: the USG foam option may sound attractive, but realize the subfloor must be dead flat/level before installation. A mud floor can correct minor deficiencies).

Like I posted earlier, if another layer of mud were on top you'd be dealing with what's commonly referred to as a liner, not a membrane.

Once you have made a final decision as to how you will proceed with your floor and waterproofing plan, you can begin to repair/strengthen your floor joists, as you'll have a good approximation as to how much buildup the floor layers will take.