Waterproof membrane 4 shower installation - always required?

[ryanjg117]

A family member is having a tub shower combo removed and replaced with a custom walk-in, tiled shower. The contractor / plumber has finished the rough-in and has installed Hardie board tile backer. It doesn't appear to be green board or any special waterproof material. In my research, I thought that waterproof membranes like schluter kerdi are always to be used, but I believe he plans to thinset right over the Hardie board and install tile. He mentioned that in his years of work, he's never had a problem with showers leaking. Does this sound right to you? Any scenarios where it's okay not to waterproof?

 

[Mortiser]

Always use a water barrier/membrane. You can paint on Red Guard, but the Schluter membrane is better. That's what I'd use.
Plumbers don't usually install this. It's typically your tile setter who does that.
Good luck!

 

[tjbnwi]

To start with, the national code only requires the pan to be waterproofed. This water proofing runs 12" up the wall. Check your AHJ for local requirements.

What is the pan material? When you say walk in, do you mean barrier free?

If it is a field built pan, all codes I know of do require a 24 hour flood test for the pan. 

Green board is old mositure resistant drywall, it is not allowed by most codes.

Minimium should be taped seams and corners with acid resistant mesh tape and mortar.

The Hardie can be waterproofed with Kerdi or a roll on membrane such as Mapie Aqua Defense or Customs Red Guard. Again this is not a code requirement. This is best practice.

A couple of barrier free, neither are ADA compliant, one curbed. The orange is Kerdi borad and Kerdi, the violet is Noble. I'm not a fan of roll ons.

Hopefully the links work....
https://www.flickr.com/gp/156063358@N08/JY1218
https://flic.kr/s/aHskApfYQP 

Pictures would help.

Tom

 

[xedos]

Does this sound right to you?

No.

Any scenarios where it's okay not to waterproof?

For me, no.  There are certainly instances where showers are not waterproofed all around the country and they function.  For a while at least.  Doesn't mean they are good or advisable.  I certainly wouldn't spend my money on them.

Questions for the plumber:

1. What did he place on the studs before he put on the hardi?
2. What did he use to fasten the hardi to the studs ?
3. How far do the boards extend into the pan he made?
4. How did he waterproof the pan corners at the curb ?
5. What did he use to make the pre-slope under the rubber pan before he installed it ?  ( I bet he didn't even use one - if not ; that's all you really need to know about his competence)

The problem with : " that in his years of work, he's never had a problem with showers leaking " is twofold.  Ignorance is bliss. And when he started I'll bet the walls were constructed of traditional lathe and mud.

Issue now with new techniques is water management.  That hardi is going to wick up moisture from the floor pan and start to mold and deteriorate because almost no one details the joint between the hardi and the floor correctly.  It's just too difficult and time consuming and more expensive by extension.  If he didn't protect/waterproof the wood studs behind the hardi - the problem is going to spread there too.

A sheet membrane like Schluter Kerdi will only be marginally better in this particular instance because the intersection between the pan/floor and the hardi walls is still the weak link.  Those membranes require a different type of drain and do not use a rubber pan material underneath the mudbed floor. 

I'd suggest you google hardiboard problems with shower pans to get the lowdown on how this shower can go sideways for your friend.

 

[Brush]

Cement backer board is used often around here for shower walls.  The only thing I can think of that you can't use anymore is just drywall.  Regardless of what you use you should always install it in accordance with manufacture installations.  Usually means for cement board, joints need to be taped at a minimum.  If it was my house/job I wouldn't stop there and probably red guard over it.  I definitely wouldnt run the cement board all the way down to the pan either.  We hardly every use cement board in any application, we use mudsets 95% of the time.  Each system has its pros and cons I suppose and most people are cheap and bathrooms tend to be expensive as it is.

 

[Sparktrician]

I recently had a customer that reported a shower surround grab bar falling off at the touch of a finger.  Investigation revealed that the grab bar was installed using plastic anchors through tile which was glued (yes, glued) to drywall.  The gaps between the tiles were so small that a thorough job of grouting could not have been done.  Additionally, there was no waterproofing membrane behind the drywall, so the insulation was soaked through and some framing members were rotting.  The paper covering on the fiberglass insulation was so badly damaged that the insulation had to be replaced along with the rotting wood.  Once the wall cavities had dried out, the plumber and I worked together to replace the faucet set and spout (which was rotting through).  I had to install serious backing for the grab bar before installing the waterproof membrane, followed by cement board and tile properly installed with thinset.  Once I'm done with this job, they're having a refinisher that I know come in and rework the tub before final caulking.  What scares me is looking at their second bathroom and knowing that the tile there was as poorly installed as the tile in the master bathroom.  This project was far more costly than they anticipated, and now they're likely going to have to do it all again.  [sad]  The builder and tile setter that did this house should be taken out and shot.

02/29/20 - Photos added.  The science project  [eek]  (last photo) was on the back side of the drywall. 

 

[Holzhacker]

Consistently 1/3 to 1/2 of the tile showers I test leak, some leak really bad, some flood the room below. If your guy isn't going to install a proper membrane on the floor then it will leak. Just a question of when. The Plumber will say his drain isn't leaking and that will likely be the case so he won't provide a repair. The tile guy well he'll be gone.
I always recommend either Schluter or Noble products. A customer doesn't want to use them, great call somebody else.
To add onto what Tom mentioned, I don't like the roll on stuff (red guard) either. There isn't anything inherently wrong with it. The problem is you are at the mercy of the grunt rolling it on. Does he do a crap job or good job.
Unless the guy installing the tile shower is a rockstar providing documentation for the install (doesn't appear to be the case here) forget the tile shower floor and buy a nice fiberglass base. There are a lot of really nice options out there if you don't just go to the big box store.
On a side note if you are installing a steam unit, you need 100% encapsulation.
Throw the guy off the job.

 

[Koamolly]

Also check...

Laticrete and their Hydro Ban paint on membrane.
https://laticrete.com/en/tile-and-stone-installation/waterproofing/hydro-ban

 

[DeformedTree]

Membrane for sure.  I'm not sure how much I trust the red-guard stuff, but it sure is a step in the right direction.

The problem with any "I've always done it this way...no problems" path is that person A) is trying to sell their method thus has a bias and very well is lying, but B) that person isn't around when their method fails.

It might not fail for years or show signs of failure for a long time.  The people the person did work for might not know the shower is bad/failing. They may have moved on and the current owners have no idea who did this job that is failing. The contractor isn't knocking on doors every year to check on how their work is holding up. Even if the contractor does know their jobs have failed, they won't tell you, and he/she won't give you a reference to someone with a failed job.

Kerdi type products came about rather recently because what tile folks were doing wasn't working. There is good reason so many companies have come out with so many products so quickly.  Old houses have tile jobs that have held up, but those are also tile over an inch of concrete on the walls, and the walls are usually open cavities so moisture can get out over time and there is nothing to mold easily.

 

[capww8]

I recently did a new shower in our house with kerdi board and the product was really cool to work with. Way easier to cut / handle than drywall or hardi board.

 

[Cheese]

Membrane for sure.  I'm not sure how much I trust the red-guard stuff, but it sure is a step in the right direction.

The problem with any "I've always done it this way...no problems" path is that person A) is trying to sell their method thus has a bias and very well is lying, but B) that person isn't around when their method fails.

It might not fail for years or show signs of failure for a long time.  The people the person did work for might not know the shower is bad/failing. They may have moved on and the current owners have no idea who did this job that is failing. The contractor isn't knocking on doors every year to check on how their work is holding up. Even if the contractor does know their jobs have failed, they won't tell you, and he/she won't give you a reference to someone with a failed job.

Kerdi type products came about rather recently because what tile folks were doing wasn't working. There is good reason so many companies have come out with so many products so quickly.  Old houses have tile jobs that have held up, but those are also tile over an inch of concrete on the walls, and the walls are usually open cavities so moisture can get out over time and there is nothing to mold easily.

What he said...there are probably few baths that leak immediately, it usually takes some time.

So 5 years later when the bath starts to drip in the basement, who do you call. The GC?  The plumber?  The tiler?  All fingers at that time point to the homeowner which seems so bizarre because the home owner has now become both the victim and the perpetrator.

So if 5 years later the leak issue crops up, I’ll guarantee at least one of these people are no longer in the trade, at least under their original business moniker.

Bottom line is someone has to take it on the cheek...the GC...not likely...the plumber...not likely...the tile guy...not likely.  The homeowner...........hmmmmm.

 

[tjbnwi]

Well--seeing as they are having this done (contracted) it can be far more complicated.

There are jobs like this I have not gotten due to the homeowner looking at just the bottom line number. If they got a few proposals and went with the one that was the cheepest without looking into the cost difference, that's on them. I've spent too many hours going over the line items on estimates (they call it-educating the customer---such a line of bs). Most only see the bottom line.

Reading the responses in this thread, there are some things mentioned/laid out that are not best pratice and should not be done.

One job I did not get was a family members---until the shower leaked into the kitchen after the 3rd shower was taken in it....

Again---there is not national prespective code that requires the walls to be waterproofed, only the pan requires waterproofing in the codes. My TCNA is at home, I'm 99.9% certian even the TCNA shows details where the walls are not waterproofed.

The family members....Once the ceiling was damaged, they called me.

Cut some drywall out, found the corner in the first photo. This was a field fabricated mud pan. The liner is well---I'd get banned from the forum if I described it the way it needs to be described....

Yep, that's a plywood wall in the shower with no waterproofing. It was 3 months since the last shower when I got to this. The wall was still wet, notice the mortar ridges, they should be full collapsed.

The curb. No membrane up and over to seal it.

Notice how wet the wall is.

At least the tile came off easy....

I can think of no way this liner could have been installed more improperly.

A few other notes;

The bench had a couple of inches of water in it when I pulled the top.

This is a water in/water out system----the drain weeps were completely blocked with mortar.

One bright spot---they did use mortar.....

Tom

 

[ryanjg117]

Thanks all. I impressed upon the contractor the importance of waterproofing, and even called the tile supplier used on the project, who also confirmed waterproofing should be used behind the tile. I gave him a few different options, including red guard. He obliged, but it annoys me that I have to impress upon him the importance of a best practice. He is a plumber by trade, but also does smaller bathroom renovations. He's been in the trade for a long time (semi-retired), and my hunch is he hasn't kept up on new building materials or technology. At the beginning of this project, I recommended him because he would be taking full ownership of the project, not just the plumbing or tile setting or finish work. Looking back on it, it probably would have been a better decision to have acted as our own GC and engaged a plumber and tile setter for the project.

The floor is a fiberglass tub, so I'm not too concerned about that.

 

[Jiggy Joiner]

Regs will differ from country to country, and region to region in the bigger countries.
We always follow regs, as our reputation is valuable to us, and we also then have a clear conscience.
I have seen some terrible damage to houses caused by shoddy bathroom installations. Rotten floor joists, damp brickwork, damage to room below often hidden for years, caused by slow but constant leakage.
So for a few years now, we have a policy that no matter how large or small a bathroom is, we apply a waterproof membrane (tanking) anywhere that will be tiled.

We use all the appropriate backer boards etc, then apply the tanking, making sure that corners are properly taped, and the top edge of baths, shower trays, and basins etc, are taped, with the tap lapping the top edge, to create a barrier. This is very important. Also any feed and waste pipes are carefully sealed and taped
Then the tanking is applied, often two coats depending on the product.

This adds expense to the job, and obviously cost but, enables us to provide a longer guarantee.
If a client isn’t happy with this procedure, we politely walk away. In my experience, if the tanking is done properly, literally leaving no gaps, holes or weak spots, it will do it’s job for many years, regardless of whats underneath.

It’s the same with basement conversions, if the tanking is done properly all is good.

 

[Peter Kelly]

Mastic directly on plywood, what could possibly go wrong here...

[attachimg=1]

 

[Packard]

When I have my shower replaced, the one-piece cast terrazzo base will be replaced with a one-piece porcelain over cast iron base.  Not as decorative as a tiled base, but no membrane required.  And will outlive you, your children and your grandchildren.

The cast iron shower pans are very popular in Europe and I’ve been told in Australia and New Zealand too.

I have no doubt that these are special order, and probably need two people to carry in and place.
https://www.kohler.com/en/products/showers/shop-cast-iron-shower-bases

A 60” x 32” weighs a little over 200 pounds and costs $830.00.

I don’t know how that compares in cost with a tiled in base, but less labor to install.

They do sell acrylic shower bases, but the one I used flexed under foot, and I would stick with porcelain over cast iron.

 

[rst]

In the early 80s I was remodelling the 100+ old cottage 24 x 36, wife's off the boat Polish built in 1920's, he worked as crossing guard in Sunbury Pa for Pennsylvania railroad.  Anyway, we were young with two very young children and not broke but week to week.  We added on the rear to add a kitchen, dining room and bathroom.  A local plumber had a storefront and sold leftover and mis bought items.  He had a neo angle fiberglass base and a glass neo angle side and door that were mismatched.  The glass was for a 2" smaller base.  As a commercial glazing contractor, I had access to 2" x 1/8" tube.  I glued 1/4" tempered masonite to the walls and covered them with marble looking Formica extending the Formica 3/8" below the masonite. I siliconed thin 1/2" x 1/2" aluminum angle in the corners.  I also covered the tube with the same Formica.  We're still using that same shower and it looks like the day I installed it.  It probably helped that the room is 9' x 15' and has a 16' high sloped ceiling so moisture has not been an issue all these years.

 

[usernumber1]

are you guys replying to a 3y old topic resurrected by some AI accounts??

 

[squall_line]

are you guys replying to a 3y old topic resurrected by some AI accounts??

[big grin]

This guy gets it.  Bonus points for the ironic name in this instance.  [cool]

 

[Packard]

I, for one, never check the date of the original post in any thread.

I check the return address on mail, but never the postmark date.

I think it is stranger to check the date, than it is not to.

Even after this thread, I doubt I will check the origin date.

(I do check the use by date on perishables, however.)