Cement tiles cracked right after laying and no idea why

[spongeblob]

Hello! Totally new here and in need of some advice: I had cement tiles ("encaustic" tiles) installed yesterday by a professional tiler. Tiles are 20x20 cm, 1.2cm thick. They used Mapei Keraflex maxi s1 adhesive. Maybe 15 minutes after laying the last tile we heard loud crack and then another and another - tiles were getting hairline cracks and by today morning about half of the tiles are cracked and we do not know why. Tiles were leveled by hand and not rubber hammer. Has anyone ever heard anything like this and may know what caused this?

 

[Dave]

Hello! Totally new here and in need of some advice: I had cement tiles ("encaustic" tiles) installed yesterday by a professional tiler. Tiles are 20x20 cm, 1.2cm thick. They used Mapei Keraflex maxi s1 adhesive. Maybe 15 minutes after laying the last tile we heard loud crack and then another and another - tiles were getting hairline cracks and by today morning about half of the tiles are cracked and we do not know why. Tiles were leveled by hand and not rubber hammer. Has anyone ever heard anything like this and may know what caused this?

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Where they sealed prior to laying. And was in rapid set or standard.

 

[spongeblob]

Where they sealed prior to laying. And was in rapid set or standard.

They were sealed twice in the factory and I was instructed by the seller to seal them after laying but before grouting and then again after grouting. I do not know if the adhesive was rapid kind, on the bag it said that you can walk on the tiles after 24h, is this rapid?

 

[Dave]

They were sealed twice in the factory and I was instructed by the seller to seal them after laying but before grouting and then again after grouting. I do not know if the adhesive was rapid kind, on the bag it said that you can walk on the tiles after 24h, is this rapid?

No that’s slow set. So wasn’t adhesive drying too fast. I’ve laid quite a few encaustics and never had them crack like that.

 

[spongeblob]

We inspected now the tiles that were not yet laid and were still in their original box and quite a few of them were already cracked (very fine cracks, almost not noticeable). Could it be manufacturing process fault maybe? All the cracks are very similar - start from the middle of the edge and almost straight to the middle of the tile, about 5-6cm long, no cracks in corners at all.

 

[Dave]

We inspected now the tiles that were not yet laid and were still in their original box and quite a few of them were already cracked (very fine cracks, almost not noticeable). Could it be manufacturing process fault maybe? All the cracks are very similar - start from the middle of the edge and almost straight to the middle of the tile, about 5-6cm long, no cracks in corners at all.

It’s from the firing process and faulty imo.