I don't believe there are any regulations about the color of the floor and wall tiles. I wanted to post, despite not knowing for sure, to give you something to think about. Having the floor and walls the same color can be disorienting if someone is ill, has vertigo, or is dizzy or woozy at all for any reason. I, for instance, have something called POTS (Postural Orthostatic Tachycardia Syndrome) that makes me feel dizzy. Anytime someone has a problem with dizziness or gets light-headed, it is always good to be able to differentiate the flat floor from the flat walls. It helps orient us in space. A true monotone look can keep a person from seeing the transition between the floor and the walls and makes recovering from dizziness quite hard. Also, as your eyesight dims with age, having a contrast between the floor and walls helps older people (or myopic people of any age without their glasses on) re-orient themselves.

I would do a darker floor. Gray would be fine, any of the darker grays or even charcoal. You can do a herringbone with planks, a mosaic, or penny tiles or hexes. I would not do a large format tile because the grout in between smaller tiles will add "grippiness" to the floor for your mother's comfort. Even if some of the floor tiles do have a higher co-efficient of friction, the feeling of hitting a grout line with a wet, bare foot will demonstrate how the grout just adds a break to the tile that puts an end to any feeling that you are going to slip. A floor that is all dark - not one that is mottled dark and light as mine is - will allow you to

do either the dark veined wall tile or the lighter wall tile. I could see my tile being too close to the dark veined wall tile you posted. See how my baseboard is too similar to my floor tile? You want more contrast than that!

I know that I saw a nice medium gray or dark gray floor hex or 2 x 2 square with a matte non-gloss finish while I was shopping, so I know they are out there.

Any other opinions on a floor tile from others?