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How much thinset is too much behind wall tiles?

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Jul 07, 2013, 05:44 AM
How much thinset is too much behind wall tiles?

I started tiling the first wall. The bottom half of the wall had a slight bow in the middle (or perhaps the two tapered corners were out). I am not sure if I overanalyzed this, but, being the first row, I tried to perfectly align all the tiles: both top and front.

The problem is that I noticed that from the corner to the middle of the wall, the amount of thinset I had to put behind tile to get them aligned increased. I am using 1/4 x 1/4 x 1/4 trowel to install 8/12 tiles on the wall. In short, the middle columns needed about 1/4" of thinset behind them to make their front line up...

I have attached a photo, expect it does not show a top view (showing the thinset band growing from one corner and climaxing in the middle).

Is there any danger of so much thin-set? Will the wall get too heavy by the time I get up? Should I have done something else (i.e. accept the slight angle in corner tub tiles)?


Jul 07, 2013, 09:14 AM
There is no problem with the wall getting too 'heavy'. The only thing you have to watch out for is the thinset cracking from getting too thick -something that is not likely to happen until it's closer to 1-1/2" to 2" thick. With the size tile you are using the ideal thickness is 1/4" (in 1/4" rows as created by your 1/4 by 1/4 trowel). If you wind up with some areas that are 1/2" thick with the top half patterned from the notched trowel, it will work fine.

The ideal is to have a perfectly smooth wall without any dips. If you know of any low areas in the wall before you start laying tile, you can fill them with a layer of thinset and let it cure, then add a second thinset layer and tile over it. The only real advantage here is that it will make it easier to keep the face plane of all the tile even, otherwise you just have to be careful not to press the tile in too deeply to those areas with thicker thinset.

Jul 07, 2013, 11:16 AM
Thank you. As usual, you've been very kind and helpful.