Shower Project

[eagle4x]

Advice appreciated for mixing thinset. My minimal experience in doing it main reason for considering the method of screwing the tiles to the wall. I installed some 12" x 24" tiles before purchasing the 24" x 48" tiles and after the thinset dried I noticed one of them did not adhere good and it started to come loose.

When I mixed the thinset for the 12" x 24" tiles I mixed it in a small bucket enough for one tile at a time. Mixing thinset in a 5 gallon bucket for 24" x 48" tiles would be even more difficult than using smaller buckets for the 12" x 24" tiles.

The 24" x 48" tiles cost about $1,200 and I don't want to mess up the job due to mixing the thinset incorrectly.

I got about 3 quotes for mixing the thinset, cutting/installing the tile and I would provide materials and have the backer installed myself. All quotes in the $1,200 range which I thought too much considering it was installing only 8 pcs of tile and with minimal cutting involved (4 tiles on one wall and holes for shower valve/head).

Since my mixing thinset skills not as good as a pro, I may just go ahead and mix the thinset myself and use the screws too just in case I don't mix/apply the thinset correctly.

[cx]

Mike, if you have the correct mixing equipment on hand and you read and follow the product manufacturer's mixing instructions to the letter, you're likely to find that your mixing will actually exceed that of many professional tile contractors. That, combined with the use of the correct trowel and its correct application, should allow you to set your tiles adequately.

I would very strongly suggest you get a helper for installing the tiles. I also suggest you watch this video showing some of the finer points of thinset mortar troweling.

Originally Posted by Mike

The 24" x 48" tiles cost about $1,200 and I don't want to mess up the job due to mixing the thinset incorrectly.

I am much more concerned that you will "mess up" one of your tiles with your hole drilling and screw mounting of the tiles. And cutting them.

I think you may find that $1,200 could be a bargain for someone to accept the responsibility for correctly cutting and setting 8 of your $150 apiece tiles once you've set a few.

My opinion; worth price charged.

[Tool Guy - Kg]

While I can’t predict the future, I know some of the weaknesses of these materials and understand how many showers fail, having torn out tons of them. With that in mind, if you drill and screw these tiles to the wall…

I see moisture passing through the grout (as it’s not waterproof), collecting in the hollow behind the tiles, then bleeding through to the front in the form of ugly efflorescence.
I see grout cracking due to the tile flexing that will occur from touching/leaning on/cleaning the wall. The increased moisture into the “tile assembly” will lead to more efflorescence to the front…and seepage to the back of the substrate into the wall cavity.
I see tiles cracking somewhere down the road due to too much flexing…possibly while someone is leaning on a wall. I hope pieces of tile don’t fall from the wall or a trip to the emergency room for stitches to the legs and/or feet are going to be necessary from the glass-sharp shards.

I’d avoid trying this experiment, if I were you. I think it will lead to wasted money and possibly getting hurt. I’d either get more estimates…or learn how to install tile in one of the many, many methods that are far more likely to last a good, long, proper amount of time. We are happy to teach you anything you’d like to know.

[eagle4x]

Bubba,

Thanks for your advice, however, not meaning to argue, but...

Grout is not waterproof on professional tile jobs with thinset and is not waterproof either and can crack regardless of type of installation. Backer with liquid membrane will fail over time even when tile installed using thinset. Use of thinset doesn't help increase waterproof properties of installation as it is not waterproof either.

If water does seep through the grout on installation using screws, then it will seep to the bottom of last row of tiles into the shower pan not through the wall since it's more likely to travel down than through the wall. If I do the installation using screws, I won't put any sealant on the bottom row of tile on the outside to help ensure any water that seeps through the grout has a place to escape.

If the foam board is installed following mfg instructions it will be 100% waterproof and therefore much more waterproof than using other types of backer where a liquid membrane is applied.

Summary:

Waterproof, even with professional installation?:

Tile - N
Grout - N
Thinset - N
Cement Backer - N
Liquid Membrane - Y, but will fail over time.
Foam board backer - Y, with proper installation.

I understand the concerns over safety and possible problems with chipping/drilling the holes. Therefore, when getting quote for shower glass installation, I'll ask installer to give me a quote for drilling the holes before tile installed since installers are pros at drilling them in tile for channels and have better equipment than me. However, before doing that, I'll buy 2 pcs of less expensive 24" x 48" tile and drill holes myself and install them on the shower wall to check if any problems with lippage.

[Tool Guy - Kg]

Hello, Mike.

I disagree with much of what you said. But it’s your house, your money, and your decision. I wish you the very best. I really do.

[eagle4x]

Hi Bubba,
What specifically do you disagree with regarding my previous post?

[eagle4x]

FYI...

One of the shower walls is adjacent to my hallway and I had to remove the drywall adjacent to it. If I decide to do the installation using screws, I'll either wait a year after installation done before hanging the drywall in the hallway or install it but wait to apply the joint compound/tape so can easily be removed later to see if any problems with water penetration into the wall cavity. Also, I won't install the grout over the screw heads in case water does penetrate into the wall cavity so the screws/tiles can easily be removed.

[Lou_MA]

You’ve gotten good advice on the proper way to proceed which you don’t seem inclined to take.

None of us can really offer advice on your preferred method since it’s not approved by the foam board manufacturer, the tile manufacturer or the tile industry.

I’d say keep us posted.

Heck, I’ve torn out tub surrounds that were tile over drywall that lasted way longer than I thought they had a right to. Maybe yours will be a breeze to install and work out fine long term with no maintenance issues.

[Gozo]

I’ve been following along and can’t resist jumping in.
Depending on your level of hurry, if you need it done very soon, and can find someone to do it, hire a pro; the decreased stress is worth it. Making nail holes is not.
That said, mixing mortar is not rocket science. As others have said, follow the directions. Go one or two tiles at a time if you have to. A Chinese 1/2” slow speed drill will power through quite a few buckets of mortar before it burns out, and the drill and mixer paddle (I like the egg beater type) will set you back ~$50 or so. If you’re worried about technique, get some cheap big tiles (my local tile place always has chipped or odd lot pieces they’re glad to part with), a slice of drywall, and practice a bit. It’s kinda fun and a good way to pick up some confidence.
I have to agree with the consensus that nails are only going to lead to regret down the road. I suspect, not too far down the road.

[SpaceCadet]

This is the look you'll end up with:


You probably need more than 4-6 screws per tile. Each hole is a stress point where cracks can start. You don't get that when you have adhesive over the entire back surface (or even spots) of the tile. Are you married to this tile? You could probably screw corian panels to the wall more safely and it will be easier to drill.

[cx]

Originally Posted by Mike

Liquid Membrane - Y, but will fail over time.

I need some help with that one, Mike.

[Mathman]

What are these screws going to anchor into? The foam go board?
Don't see how that would ever hold. Put studs behind the go board where every screw will go in from the tile? Use toggle bolts or some other type of anchor? I can't believe the foam go board could ever maintain and hold those size tiles without being able to screw into a stronger support like a stud.
That would take a lot of planning to get studs in the right place for the screw points each tile.

I can't help but believe if you follow through with this plan you will be screwed.

[ss3964spd]

Good point regarding the studs, Kirk. There would need to be a lot of them, especially if the screws were placed 1.5 to 2 inches in from the edges. There would be no "sharing" a single stud. Toggles won't work, nor insertable anchors. 1/4" of ply behind the foam would be insufficient to hold a screw.

[eagle4x]

Kirk,
Both the foam board and screws though tile would be screwed into studs, some are 16" on center and some less.

Additionally, I'll be installing the foam board horizontally and there's 6" blocking at bottom of studs where shower pan and also on 2 rows above at 3' (board is 3' wide) in order to give better support.

[Mathman]

I just can't imagine adding more studs is easier than mixing. Also, most 24 by 48 tiles are something like 23 and a fraction. Seems like you would have to add a stud to each side of the current studs and then some in the middle for the center holes. And if you don't place the studs in the right place your holes in the tiles won't line up with the studs.

Seems like a lot of work. Good luck.