Ulraflex II thinset

Recently had a tiled shower pan installed and noticed that the thinset is coming up thru the grout lines. Contractor says that I bought a bad batch of thinset that never setup properly and the tile will have to be taken up and replaced with a different type of thinset at my cost!

Does this sound right or maybe error on the contractor?

All-
Thanks for the responses. The thinset was a pre-mix thinset. After the job was completed I waited a few days before I was able to start using the shower. Painting, drywall, ect. After a few days of using shower I noticed something oozing up from in between the tile grout lines. Upon better inspection I noticed a section of the tile wasn't grouted properly and was cracking and you could feel some movement in the tile which caused the thinset to ooze out. Should the thinset setup (harden) after a few days? Maybe with some water getting between the tiles and mixing with the thinset made it unset (lack of better word). If I re-grout the bad area chance that may solve problem?
Thanks again.

If I understand correctly, premixed thinset was used on the shower floor? If so, I'm afraid you are due to have the floor redone. Premixed thinset is not thinset at all, it is mastic---glue. It reemulsifies with water.

Where are you getting the Ultraflex 2 title from? That's not a premixed product. Premixed products have a very limited use and while they all make some outrageous claims on the buckets, they all say "not for shower pans"

So, the product turned to mush when exposed to moisture. It performed as expected. Your low bid contractor used the wrong product.

This sounds almost identical to the other recent post. Ultraflex II is not a premixed grout. Please look at the other topic in the forum under Ultraflex II.

Good luck!

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