re: Need help, I’m retiling my bathroom

quote:

---

DavidTheGnome

---

While I used to set tile professionally, this should not be considered professional advice since I haven't been to your house.

What you are taking up is mosaic tile most likely set in a fresh mortar bed. The way they used to do this was to install the metal lathe (wire underneath the mortar) tacked to the subfloor, then screed in the level dry pack mortar bed. As it was curing, the tile setter (prolly some small Italian dude) would work from kneeling boards and spread and dampen portland cement on top of the curing mortar and set the tiles directly into that. The whole system would cure together and it was VERY EFFECTIVE (as you noted the tiles stuck wonderfully).

Later, with the onset of "Thin set" mortars, they began to screed the mortar bed and let it set, coming back the next day to set the tile (using the thin set). This works well but you can chip these tiles up without damaging the mortar underneath by removing the grout and attacking them from the side. The thinset has good adhesion properties but can fail in lateral sheer.

Now, given you have removed your dry pack mortar bed, it must be replaced with something. Whatever you do must be the same thickness (or near based on the thickness of the replacement tiles) as the old bed as the base tiles of the walls should be at the elevation that works with the floor tile thickness you will be installing. Best would be to go back in with dry pack mortar. In fact this is the only thing I would do. I cannot imagine that you would be able to "sandwich" enough wood layers (or otherwise) to get to the correct elevation (with precision).

You are going to need to remove your toilet, as your new tiles should go under it. Whatever you do around the toilet will have to be very sturdy as the toilet should not rock or move which will cause a leak.

Based on what I have seen in this thread DO NOT frick WITH YOUR SHOWER ENCLOSURE. You have no chance of it not leaking when you are through. Thakfully for you this appears to be the bathroom floor but not in a "wet area" like the shower which would require a water barrier like a "Pan" or one of the newer roll on applications. Good luck, there are videos on youtube.

here is one that shows hom to mix the mortar.

You need to watch this plus a bunch more.

I can answer specific questions if you have more.

ETA: This dude looks like an experience tile setter showing you how to install the dry pack mud floor

He is installing a shower floor which must slope to the drain. Yours thankfully, should be level. The way he mixed the mud is exactly how we used to (except we did not use quickcrete (but you can).