Neighbor redoing bathroom from the 1950 era. Think about 9”
Ceramic tiles. Should the floor tiles be the same as the wall tiles?
Can the existing floor tiles, be covered over without removal.
Appreciate your input and opinions. See the enclosed pictures

You can use floor tiles on a wall but not the other way around. Those tiles are 4", not 9". You can put tile on tile on the floor but the base must be very straight and not cracked. You will also have an issue with the toilet flange, it will need to be raised as well as the door threshold and possibly have to cut the door. Do not recommend doubling up wall tile, it eliminates the tub flange and is hard to fit the tub spout and handles, sticks past the window etc. A house that age most likely has a poured cement base, not backer board. I would not recommed the same color on walls and floor, would look like walking into a ceramic box.

Great Information Thanks

Thanks