I wonder why? What were you using to rinse off the floor... something that made it temporarily slippery? Did they get slippery when wet in your older downstairs bathroom too? We have 2" smooth matte porcelain tiles in our remodeled shower and our feet don't slip. Those replaced 4" square matte ceramic tiles from 30 years ago. They didn't slip either. Bigger feet? Seriously, in our guest bath (tub with shower) we have a very lightweight shower mat made out of thin foam like material. Just plop it down when you take a shower and hang it up by its loop on a Command hook (made for wet places) that you can mount anywhere inside the shower. Bed bath and Beyond has them. I fear that anything you do to the tile itself will cause a lot of problems with cleaning it. -Babka

My friend Nancy had the same problem in her bathroom. She used a company called Johnny Grip, she said it worked really well. I think the site is www.slipperytile.com you can try it out, it worked for her. Here is a link that might be useful: slippery tile

You could install a sanded epoxy coating over the tiles. It comes clear (although it doesn't sound like you want to look at the tile) or in any color you want. I would suggest having a professional do the work, but it's possibly a DIY project. There is also a spray-on product available. I'm not sure if it is okay for outdoor use, but I've seen it for indoor use. I'm afraid I don't remember the brand, but you can do a search for anti-skid coatings and I'm sure it'll come up.

DalTile has a huge selection of unglazed porcelain mosaic tiles in the classic hexagon and 1" squares, and basketweave. I've used them before in baths and loved it. Here is a link that might be useful: DalTile Mosaic tiles This post was edited by lazygardens on Thu, Jan 10, 13 at 8:47