https://youtu.be/QAcUAHe4UEc?feature=shared

It should be thank you.

Has to be for large format tile and aslo an installer who has experience with large format tile and you talk to the references , Those hollow areas will crack very quickly

When you move outside the norm you need to put in a lot, a real lot more personel prequalification, self-education about technique and onsite supervision/evaluation of the tiler. You may need to cut his work immediately at the begining and search for someone else. It's reality. Sounds like this proves that point.

We had 1800 sq ft of ceramic tiles fail due to improper installation over Gypcrete. It was after we’d purchased the home, and we noticed hollow areas. We ripped it all out and hired a pro who does large flooring for buildings and schools etc. I think they used a crack mat over the Gypcrete after resealing the gypcrete, then covered every inch of the crackmat with the usual tile adhesive material, like mortar or whatever it’s called.

any pics of the tiler applying mortar to the backs of the tile?

for that size, 95% coverage is required. 100% is best. (and the wall is also trowled)

a lot of lazy tilers use the Spot Bonding Method. basically 4-6 blobs of mortar that they then just stick on the wall. NOT allowed for heavier tiles or vertical placement in a shower or fireplace. (they can fall off and hurt someone)

do all of the tiles have hollow sounds?

did you ask about their method?

talk to the contractor?

https://stoneforensics.com/debunking-the-myth-do-hollow-sounding-tiles-signal-an-imminent-floor-failure/

^^^ Interesting article. I've always heard that hallow sounds = improper installation.

I had 4x12 slate tiles installed by a contractor (his sub) and some of them had hallow sounds when tapped. A couple months later, I saw the first crack in one of the grout lines. The cracks in the grout have continued - however, none of the tiles are loose/broken.

We will have the floor replaced eventually - I'd like to wait until after my kitchen and powder room renovations have been completed. If I'd have noticed the hallow sounds prior to paying for the work, I would have required the contractor to have the floor to be replaced (by a different tile installer). If that wasn't done, I wouldn't have paid him.

In my state of residence, a right of remediation is required before a homeowner is able to sue a contractor.

Just had an inspection. Waiting for report.