I'm installing a new ceramic tile floor in my kitchen. I've installed a cement backerboard and now the floor is raised the height of the tile. This isn't a problem except where it meets our sliding glass door. If I tile all the way to the door, the tile just ends right inside the door track and sticks up a bit. This doesn't look so hot and leaves the grout exposed at the end of the tiles. Is there any way to better finish the tile edge there? I've looked into a marble threshold and don't really like the idea but I guess I could live with it if I could find a piece long enough for the door. Any suggestions out there would be appreciated.