I am about to start tiling a concrete area of my home about 220 sq feet. I was wondering if there is any specific type of thinset I should be using for a concrete surface. The tiles will be 12x12" ceramic tiles.
I use this type of Flexbond for concrete applications - well most applications. This will isolate cracks up to 1/16th of an inch. Also this stuff really bonds well to concrete. I know that you can buy that $10 bag but I wouldn't skimp on the thinset. I can say I have done a lot of tiling and not a crack yet (knock on concrete).
Also want to mention that I end up doing a lot of glass mosaic patterns (even in floors) and this stuff (get the white for glass) works great.