durock or green rock for shower

[clare]

Except housewrap is water repellant and not moisture proof. It is designed to breathe and pass moisture freely.

[Mayayana]

| Just use the shluter system and be done with it. 100% water and | moisture proof. No second guessing.

I'm about convinced that you have stock in that company. I see no reason or even logic for it, other than to make lots of money selling the allure of "cutting edge technology".

[Mayayana]

| The coating is over the board, board tape, and thinset applied at those | locations.

Yes, I understand that, which is why I said you're losing the mortar integrity. You're gluing your tile to a plastic coating rather than getting a thinset -> concrete bond.

| The redgard keeps any moisture that gets through the grout from | getting through the concrete board. Then it either has to find its way back out | through the grout, or find a path, hopefully back into the tub area, through the | caulk at the bottom of the tile. |

That sounds like Redgard marketing hocus pocus to me. Tiling on mortar has been done for thousands of years. Why, all of a sudden, is grout considered to be a non-waterproof material? Even if tiny bits of moisture can go through some grout, the concrete board is designed to let it migrate out. The top of the concrete board is not plastic wrapped.

I've been doing the same for years and never had a problem. I also built a steam room about 12-15 years ago. It's been heavily used with no sign of problems. Just as nearly every other steam room ever built has been some version of tile on mortar and has worked just fine. If moisture were getting through then even steam rooms built with concrete wall on metal lath would eventually break down.

The Shluter system is, in theory, similar to the Redgard approach, except that it would provide full waterproofing where Redgard probably won't. But it's also similar in that it's a plastic sheet glued to the wall. So the tile is only as stong as the bond between the thinset and that plastic sheet. The Shluter people even show their sheet being used over drywall! In that case the bond depends on tile -> plastic and also plastic -> paper. That seems idiotic to me. And why do they claim it makes sense? Just to keep the moisture barrier on the front side of the wall, with the theory that otherwise the concrete board will somehow get wet due to water leaking through the grout. The reasoning just doesn't hold water, so to speak. :)

| The plastic you suggest would likely create a problem with condensation into the | wall/floor space below the plastic, or the same potential water issue at the | caulking at the bottom of the tile. |

No, because the plastic is sealing it out. The plastic comes down behind the concrete board and the gap gets caulked before tiling. It's always possible that water can get through -- at the top of a porrly caulked tub or around a poorly sealed mixing valve, for instance. But in general a plastic sheet is going to provide a good seal.

[Tekkie®]

[e-mail] posted for all of us...

+1

[Tekkie®]

Mayayana posted for all of us...

-1 He resoning is: because it works.

[clare]

No stock in the company, and this "cutting edge technology" is about

30 years old.

It works Period. It is a small part of the cost when you consider the labour and everything - and it GUARANTEES you don't need to redo it in 5 years because you guessed wrong and used the wrong stuff trying to save $50.

[clare]

Grout has ALWAYS been considered a non-watertite material.

It's your job and your choice. You will do it your way regardless. If it works for you, that's all that counts. I'm just saying if someone who has not done it many times your way wants to do the job and be SURE the job is done right, Shluter is his best friend.

[Ed Pawlowski]

It works, a very important part of the job. We opted to use Swanstone bases rather than tile on the base, but if not, Schluter would have been used.