Nope. Rebuild it.

Nope, its a tear out and a complete redo.

The pain of redoing it now pales beside the pain of future water damage, mold and falling tiles if you don’t.

Sorry, nope, total do over with someone who knows what they are doing.

It’s a gut job now. So sorry.

There needs to be a poly vapor/waterproofing barrier behind the Durock or one applied to the surface before you tile. Just rip it all out as your contractor obviously had no idea about water proofing a shower. Pictures would be useful.

Woah up on that demo please. "Durock will not swell, soften, rot, delaminate or disintegrate if exposed to water." People here hate when I quote USG's installation instructions, but they clearly say that waterproofing can be used "if desired". Page 3.

Please stop with your campaign to spread misinformation. If waterproofing is desired, then it must be added to the Durock, as Durock is not waterproof. That is very clear in Durock's literature. What you so clearly choose to ignore, every single time, is that not only is waterproofing "desired", it is necessary in a shower.

@catbuilder Common sense and local codes dictate that a vapor barrier must be used with CBU in a shower. Pedantically misleading posts should be ignored.

"Durock is not waterproof."

catbuilder:

You are correct, however, Durock will not swell, soften, rot, delaminate or disintegrate if exposed to water according to USG. That is very clear in Durock's literature.

desired

/dəˈzī(ə)rd/

Learn to pronounce

adjective

1. strongly wished for or intended."the bribe had its desired effect"

There is a difference between "desired" and "required". I suggest you famalarize yourself with each please:

require

See synonyms for require

Translate require into Spanish

TRANSITIVE VERB
[WITH OBJECT]
1Need for a particular purpose.‘three patients required operations’More example sentencesSynonyms
1.1Cause to be necessary.‘it would have required much research to produce a comprehensive list’More example sentencesSynonyms
1.2Specify as compulsory.‘the minimum car insurance required by law’More example sentencesSynonyms
1.3with object and infinitive (of someone in authority) instruct or expect (someone) to do something.‘you will be required to attend for cross-examination’More example sentencesSynonyms
1.4require something ofRegard an action, ability, or quality as due from (someone) by virtue of their position.‘the care and diligence required of him as a trustee’

If you don’t want your home destroyed, you kinda require waterproofing in wet areas. As does TCNA standards. Advocating against industry standards gets you derision, and downgrades any peer respect you may have built up in the past as a expert in a 1% field. Everyone lets flatearthers believe what they want, but no one joins them in their delusion, unless they are uneducated and gullible both.

@Joseph Corlett, LLC - this is absolutely ridiculous.

One can desire waterproofing where not required. I even called USG for the clarification and they stated the literature says desired because consumers may want waterproofing in areas that don't require waterproofing.

I suggested you call USG and you kindly declined noting the person probably was an underpaid hourly worker and not an engineer. You then ignored it when I pointed out technical writers are not typically engineers either.

Durock is not waterproof. If you want a waterproof surface, a.k.a. desire a waterproof surface, then you must add it.

bry911:

This is what USG says in writing when you ask them if waterproofing is required.

Flatearther.

Verbo:

I am not "advocating against industry standards", I am reciting USG's installation instructions. If a call for nuance in the face of a mob insisting on demolition who hasn't or doesn't choose to understand the properties of a particular product loses me peer respect, fine by me.

No, youre being deliberately obtuse and stubborn because you want to be. Get out that TCNA manual bro. You need a refresher course or two. Your pride in cantankerous ignorance and pontification is showing.

Interesting.

Having noted that @Joseph Corlett, LLC is wrong about the waterproofing, it doesn't mean he is wrong about tearing out the wall.

There are plenty of shower walls in the U.S. that are not waterproof and don't have mold problems. For years the trick was to paint drywall with a gloss paint before tiling and I have torn out dozens of shower/tub combos built in the 60's using porcelain tile on drywall and seen no water damage after 30 - 40 years.

Porcelain tile walls with modest grout lines are fairly resistant to water intrusion. Having said that, if budget and time permit, I would redo the walls.

@Joseph Corlett, LLC - you are not reciting their instructions you are using a quote from their instructions in an interpretation.

Since this is a semantics debate... recitation means reading what they wrote word for word without additions, embellishment, or interpretation. When you start pushing your interpretation of that reading you are not reciting their instructions.

Here is my interpretation of the meaning... if you desire a waterproof project, you must add waterproofing to Durock. Incidentally my interpretation was echoed by USG when I called. We should note the phone number was also in the instructions.

You can either redo it now or wait and see if it fails and redo then. If you wait and it fails, you will most likely have more damage depending where the water traveled to. Or it may never fail.

It should be common sense that Durock used in a shower should be waterproofed. Anything used in a shower should be waterproofed. But the shower we just ripped out (50 years old) had no waterproofing anywhere. It had a shower base and tiled walls. I thought for sure we would find tons of mold and damage behind the tiles but there was none.

Good luck!

• "Should USG Durock® Brand Cement Board Panels be waterproofed in wet area use?
• Water does not affect USG Durock® Brand Cement Board, however, TCNA guidelines recommend the use of a waterproof membrane in wet areas."

Doesn't it seem odd that USG could easily have said something like "USG requires following TCNA specifications." following their last sentence?

They did no such thing and it's conspicuous in its absence. Why didn't they do this? I'm betting it's because saving contractors the time and expense of unnecessary "desired" waterproofing is a competative advantage.

And a question to the demo gang: Since Durock will not swell, soften, rot, delaminate or disintegrate if exposed to water, upon what is your demolition recommendation based please?

Verbo:

I love it when my interlocutor's arguments are so weak that he has to go ad hominem. And since we're recommending reading to each other, I'd suggest you familarize yourself with the rules of this board.

As I understand it, the issue is not whether Durock will "swell, soften, rot, delimitation or disintegrate" but whether the structure and materials behind it will do so.  That's why the manufacturer explicitly states that, if you want waterproofing, you need to add the membrane.  Personally, I want my shower waterproofed. If a contractor said it wasn't necessary, I'd be looking for a new contractor.

The OP must build to local codes. Those will almost certainly require a vapor barrier between the shower and any framing and insulation. If local code omits a vapor barrier they can leave the dubious work alone and deal with any consequences later on, it's their decision, but only if they are not constrained by the local building codes.

@Jeff Meeks said, "Your peace of mind is worth more than the cost to redo dubious work."

While well meaning, this is simply not true. Your peace of mind may be worth more than the cost to redo work or it may not be, depending on several factors. If you take this approach with everything in a house then you would need to practically tear down your entire house and rebuild it every 10 years.

My refrigerator is functioning properly but is out of the warranty period... should I spend money to replace it for my peace of mind? My roof was installed 12 years ago, it isn't leaking and has never leaked, should I replace that too for my peace of mind? How about a shower that wasn't waterproofed properly...I have a shower that I am pretty sure wasn't waterproofed properly, I had access to the back of it not long ago and there were no signs of leaking at all, should I tear out a shower that hasn't leaked in 12 years and fix it for peace of mind? People on these sites are really great at spending other people's money. In reality, their house isn't perfect and they are also making decisions on what they can afford to replace.

It is generally wise to do things right the first time, if you are tearing your shower out it just doesn't make sense to rebuild it improperly. However, when that becomes impossible you need to evaluate your situation from where you are now. The fact that it wasn't done right the first time is immaterial, you now have to decide if the cost of redoing it properly exceeds probable cost of not doing it.

----

This same thing goes for code compliance. The cost to bring your shower up to code should be weighed against the cost of not bringing your shower up to code.

----

My advice was and remains: if redoing it is in the budget and the tile is not on a massive backorder, you should redo it. I would personally leave it alone if it was not in the budget or there was an excessive backorder and take the risk. It is not really a big risk and is not likely the biggest risk you have in your home right now.

Bottom line for the OP. If a shower is properly waterproofed then you could be able to take a shower in it even if it wasn't tiled and grouted. There is no topical stuff you can brush or pour on to make tile waterproof as you need to have it waterproofed BEFORE tiling.

@bry911 Your comparison of not replacing an old, working fridge to using a shower you know has no vapor barrier or waterprooding on the wall isn't very fair because the consequences and modes of failure are so different. But I'm speaking from a personal perspective and being an engineer working in aerospace I have been conditioned to always build with a degree of redundancy and safety in mind and to always follow the "codes". The OP has to understand the risk vs the costs and make their own decision.

Isn’t the risk mostly where the backer boards are (or aren’t) butted and screwed, and join the floor? Is it really likely the inept handyman did that well? And that the OP can now DIY a watertight floor without removing wall tile?

@Mama Cita Water isn't always a liquid. Without a vapor barrier a shower wall system will be permeable to water vapor that will condense on cold surfaces behind the wall such as wood framing and exterior insulation. This creates a moist environment ideal for mold and rot. In some circumstances you might get away without a vapor barrier, ie if you don't use the shower much and there is sufficient air flow behind the wall to dry it out. But if you have an active water leak in a corner or where the wall meets a horizontal surface, air flow won't help.

More interesting stuff.

@Jeff Meeks - "Your comparison of not replacing an old, working fridge to using a shower you know has no vapor barrier or waterprooding on the wall isn't very fair because the consequences and modes of failure are so different."

First, you conveniently ignored the question about the shower. Should I replace my shower that is not waterproofed and is not leaking after 12 years? The answer, of course, is no.

Furthermore, the modes of failure are irrelevant, only the consequences and likelihood of failure. The damage, in dollars, of a failing refrigerator, is not dissimilar to the damage, in dollars, of mold in a wall cavity and is likely much more.

Finally, you note, "The OP has to understand the risk vs the costs and make their own decision." That is the exact opposite of what you said and is actually my position. You said, "Your peace of mind is worth more than the cost to redo dubious work." That is not understanding the risk vs. the costs and making your own decision, that is pretending that the risk is higher than any cost.

This thread is largely just exaggerating the actual risk and damage of this problem. Without any waterproofing a 4x4 porcelain tile wall with modest grout lines is going to let through incredibly small amounts of moisture. Add Durock and you are likely to produce nothing but extra humidity in the wall cavity. Statistically, the most likely damage is going to be mold growth that can be wiped off with vinegar in 15 years when the shower is redone again. There is a chance of having to chisel out a small amount of the bottom plate and a small portion of studs which would be sistered to new studs before removing, we are talking an additional $200 in fifteen or twenty years.

"Does durock need a vapor barrier?

I called USG,the maker of Durock cement board Next Gen, and they advised using no vapor barrier so that the wall cavity can breath and allow any moisture to evaporate. Their online instructions/diagrams show no use of a vapor barrier."

Hmmm...

OP, follow your local codes, not what anyone is saying here, even me...when a discussion becomes more about the participants and less about your problem it's time to ignore it and get advice elsewhere.

You are pretending to take the high road, but really just advocating for your position.

The problem, of course, being that the IBC allows tile and sealed grout as an acceptable waterproof enclosure. So you are actually advocating against your position.

The building codes serve an important purpose but shouldn't necessarily be the only source for quality.