Author Topic: Tips for laying mosaic tile  (Read 279 times)

Le Poisson

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Tips for laying mosaic tile
« on: February 24, 2021, 10:25:39 AM »
Hey braintrust, how's it going? I'm looking for tips and tricks for setting mosaic tile in a shower stall.

It's been about 15 years since the last time I tiled a shower floor, and I'm looking at doing another one in the next few days. I have the preslope and moartar bed in. Now I'm getting ready for setting the tile. (This buildup: - no it is not Kerdi, no I am not asking about the merits of the kerdi system or mud pans versus steel pans, I am just asking about setting the mosaic tile.

We are getting ready to lay the mosaic, and I want to do it with as little mastic getting onto and between the tiles as possible. I've done a bazillion normal tile jobs including floors and walls and tub surrounds, but mosaic... not in a long time. I have seen tips to use a sheet of 5/8 plywood as a press to set the tiles flat. I have seen many warnings about not getting the mud on the tiles or it will make a mess. I have not seen much about preventing the actual mess from happening. I am open to any and all ideas to keep the tile clean as I lay it.


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Re: Tips for laying mosaic tile
« Reply #1 on: February 24, 2021, 06:40:15 PM »
I like doing tile too but I 100% would enjoy hiring this out. Good luck if you go forth. It's so easy to get the thinset stuck high between the tiles. You can use a deck of playing cards and credit cards to get it out, and pick a grout that matches the thinset honestly helps.

Jon Bon

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Re: Tips for laying mosaic tile
« Reply #2 on: February 24, 2021, 07:09:40 PM »

I'll be that debbie downer...

So yeah every tile job I have done has never been good enough for me. So I get to look at the mistakes every time a take a shower which is just great.

How confident are you in your abilities on this one? I've learned the hard way the stuff that shows and takes decent skill like tile, drywall mud, and trim its often best just to spend the money?

They do make a grout saw I forget the name? Basically a blunt utility knife with diamonds on the sides to get out the mud. As I am sure you know, get to scraping that mud out the sooner the better. Obviously the 1st 24 hours its easy to do, after that you never want to look at thinset again...

I of course take my time getting the thinset out, and when my grout goes in I get to see how much thinset I missed!,up%20to%201%2F4%20in.&text=Backed%20by%20the%20RIDGID%20Limited,up%20to%201%2F4%20in.


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Re: Tips for laying mosaic tile
« Reply #3 on: February 25, 2021, 02:42:27 AM »
First would be the actual mix of your mud, not too soft and squishy.

Then your trowel, the deeper the notch the more mud you're putting on the floor. Do a quick test on a scrap of plywood or equivalent: spread mud, press in tile, too much mud squishing up through the tiles use a thinner notch.

Spread your mud first with the flat edge of your trowel, then go over it with the notch side, do a careful job here. Go over it with the notch side more than once if need be.

The place you are most likely to have buildup due to too much mud is along the walls. I like to "cut" the edge of the mud near the walls with a small putty knife held at an angle. You're basically removing some of the mud right near the wall tiles.

I use a small J roller (hard rubber) for laminate countertops sometimes to press small tiles into place, but be careful with too much pressure.

I like the little wedge spacers a lot. I like to lay out and pre cut because I hate running to the tile saw with a floor setting up.

Remember, it always looks better with grout!

Le Poisson

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Re: Tips for laying mosaic tile
« Reply #4 on: February 25, 2021, 10:44:15 AM »
Thanks for the tips folks - "Hire it out" is probably the best, but the die is case, the project is in motion, and well, here I go...

@Jon Bon - I too am never satisfied, and I always hear my father in my inner ear harping about "that's not professional work" - I need to stop carrying his baggage around. He's not a professional, I'm not a professional, of course this isn't professional work. This is weekend warrior work.

That grout knife is nifty doo-dad. I'll look for one at HD tonight. It would likely offer much better control than the diamond blade on the oscillating tool which I have been using for similar tasks. For the record, the Osc. Tool works really well and really fast, and really scratches up the face of your tiles if you slip with it.

@sonofsven - Good tip on mixing the mud - do you get better control with the polymer mud or with the additives? I believe the trowels I have range from 1/2" notch to 1/8" vee. Good tip to test on scrap with different trowels and mud to see how it goes. Also a good tip on feathering/tapering back to the edges. I think I have a similar roller for wallpaper seams. Will have to check.

I'm also a big fan of these wedge type spacers, but I thought that with the mosaic they wouldn't work. I thought they were for leveling "regular" sixed tiles. They do make amateur work look really good though.