We had our kitchen floor tiled with a fairly pricey tile. The tile has ruff edges. The initial job looked great but after a year the grout started to come out. I went and bought a latex additive, removed the grout and regrouted. A year later the grout is coming out again. We had left over tile and when we re-did the Half bath, my wife had a different guy, tile the floor with leftover tile. 18 months later the grout is coming up there too. Any suggestion short of ripping out the tile would be appreciated.