Hi, I'm new here. The house I bought was built in 1979. The kitchen has a tile floor. But not the regular tile. It has about thousands of small pieces of tiles put together like kids' puzzle board. The spots of high traffic have loose tiles. I bought a bag of Flexbound from Home Depot. As I tried to fix it, I found what's under the tiles was something like powder, not like solid and hard background. I used vacumm to eliminate the powder and filled it with Flexbound mixture. Wait for about 12 hrs, it worked. But the problem is I cannot use just a single layer, its' much more than that. Because I had to fill over a inch deep after the powder is gone. Can I use cement to make it flat then use Flexbound? Thanks in advance. Take care.