Time To Ask The Professionals: Tub To Tile Sealing

[cx]

Red Screamer is the common description lovingly(?) used to describe those MK saws that use the angle grinder for power. If you've ever actually used your saw, we figgered you'd recognize the description right away.

[ss3964spd]

My Red Screamer, an MK 370 EXP, in all its wonderous glory.

[Tiger Mountain Tile Inc]

You can cut both holes with your angle grinder. The 23mm hole will need to be cut from the back.

FYI, the standard hole for pipes like that is 1 3/8 inch. That's around 38mm.

[PGB1]

I apologize for not replying sooner. For some reason, I don't get e-mail notifications of threads to which I've subscribed, so I missed the new answers you all gave.

Thanks for the explanation of Red Screamer. I've used my saw hundreds of times, but still didn't connect the name. I refer to mine as the "Oops, I missed the line saw".

Thanks, too all for cutting methods. They'll come in handy.

[PGB1]

I apologize for abandoning this thread. Life got in the way of the project. Soon, hopefully, I can re-start.

I have a tub-to-tile follow up question & hope you all don't mind that I put it in this thread. (Wasn't sure if it was supposed to be here or a new thread)

The cement backer board will get Mapei Aqua Defense. Then it will be tiled. The tile "we" will most likely choose does not have trim pieces, therefore the bottom row's bottom edge will be raw edge ceramic.

My question is: Should I seal the tile's bottom edge to the tub?

Reason For Asking: if the tile is sealed to the tub, when water gets through the grout and rolls down the backer board won't it get trapped by the sealant?

Is it best to not seal the bottom row of tiles to the tub?
If so, how do you professionals handle the bare bottom edge of the bottom row? Is it simply left as-is?

How high above the tub does the tile stop? (The cement board is about 1/4" above the top of the tub.)

Thank You for your patience as I learn.
Paul

[cx]

Originally Posted by Paul

Reason For Asking: if the tile is sealed to the tub, when water gets through the grout and rolls down the backer board won't it get trapped by the sealant?

And a very good reason it is, Paul.

The tile industry standards call for use of a flexible sealant in that joint. The problem with that, and the reason I don't follow that recommendation, is exactly what you've described. And I have removed the sealant from such joints and had a small flood of water come out of the wall.

I've always grouted that joint, telling the customer that the grout would crack and if it became unsightly, I would return and replace it. That was back when the only good option for a sealant was the shiny, clear silicone. Today, with the availability of color-matched, and texture-matched silicones available, the appearance would be good and I'd be inclined to use the sealant, but allow for several gaps for water drainage. Keep in mind, that is:

My opinion; worth price charged.

[Edit] I would have the tile come down low enough to cover the edge of the CBU, but still at least 1/8th" above the tub.

[PGB1]

Thank You CX for sharing your experience with the tub sealing.

I like both of your plans: Grouting or sealing with gaps. I'm the customer, so when re-grouting is needed, it'll be no problem. Perhaps I'll try grout first & see how it lasts. I'll also be sure to drop the tile past the end of the backer.

Thanks Again,
Paul

[ss3964spd]

As it's been said in these pages, Paul, it isn't much of a question of if that grout joint will crack, just a question of when.

Another option to consider. If you are installing a glazed ceramic tile, or a porcelain tile (both having low moisture absorption rates through their faces) you could use a water proof grout and silicone caulk for the tile to tub joint (as well as the inside corners).