Well I am guessing that horzontal will give a wider look and vertical will give a taller look, kind of like clothing principles when wearing strips.

Have you factored in the desired surface that one tiles to; i.e. waterproof membranes, cement board, special system for the pan, etc? The items dollar up I gather.

If you lay the tiles horizontal there will not be 3 full tiles across. Is that going to bother you? I like your simple layout plan BTW. I think "less is more" is a beautiful thing.

With a 36" square shower, I'd suggest laying them out horizontally to visually widen the space. I prefer offset layouts (we went with a similar size, 12 x 18's, with a 1/3 offset).

Here's a photo from Houzz that might help visualize this. These look like 12 x 18's to me and it appears that the portion of wall in the shower that is visible would be about 36" wide, the size of yours.

[contemporary bathroom design[(https://www.houzz.com/photos/contemporary-bathroom-ideas-phbr1-bp~t_712~s_2103) by baltimore architect Ziger/Snead Architects

Thanks so much for your quick responses!

Enduring--I was thinking the same thing about making a small space appear larger by running things horizontally. I stopped wearing horizontal stripes long ago!

Treasure--thanks for posting the picture. My DH would like the offset. I was thinking it would be too busy, however, looking at the photo, maybe I'll change my opinion.

Any more photos?

Keep in mind too that the size and color of your grout lines will affect how busy your tile will look. If you go with minimal grout in a color with less contrast to the tile color, it will blend in more.

This gray shower doesn't have an offset but I think it looks less busy because what little grout lines there are blend into the tile color.

[modern bathroom design[(https://www.houzz.com/photos/modern-bathroom-ideas-phbr1-bp~t_712~s_2105) by edmonton architect thirdstone inc. [^]