Build-up Needed for Tile Installation in Shower

[robertlair]

I am doing a shower tile installation on mold-resistant drywall and I am waterproofing with redguard. The drywall comes down and sits on the shower edge/lip, and the tile will go over the lip and down to the base of the shower. All looks great except one of the studs was a little bowed and one of the bottom corners of the shower has a small section where the drywall doesn't come out over the lip which will prevent the tile from being able to sit correctly. As a result I need to build up this section. The section tapers from about 1/4" short to 0" over a 1' x 2' section, where I need to build it up. My questions are:

1) Can I use thinset to build this section up?
2) If I do, should I apply thinset before or after the redguard?
3) If not thinset, what can I do to build this section up so the tile will sit right?

Thanks!
Bob

 

[Tile Marble Granite]

send some pictures that might be a help to us

 

[robertlair]

send some pictures that might be a help to us

So I have attached two photos, IMG_3767 shows the drywall that isn't quite covering the shower lip (I put flashing tape on for additional water proofing). Then in the second image IMG_3769, I put up a piece of tile so it is level with the shower edge and you can see the gap I am dealing with (at its worst I am dealing with about 1/4", but tapers away in about 2')

I have had one person now tell me that I should just waterproof like normal (without any build up), and in that corner just apply more thinset behind the tile. I just didn't know the best approach, as I was worried a large amount of thinset could break off, etc.

Thanks so much for your advice!
Bob

 

[Tile Marble Granite]

oh I see clean up the area, get some acrylic primer from Home Depot Level Quick would do, soak in the bottom portion of the drywall let it cure overnight, then get yourself some Schluter Kerd Fix and fill up the gap and let it cure overnight. You should create a seal along the shower pan using the Schluter Kerd Fix. S K Fix is an elastic adhesive very good for building bathrooms and showers. Do not use silicone.

 

[Kakers]

I have a similar problem. Should I start a new thread?

 

[send pictures]

I have a similar problem. Should I start a new thread?

 

[Tile Marble Granite]

I have a similar problem. Should I start a new thread?

send pictures