Backer board installation

[kdaniels]

Hi. I am new to the forum but need an answer. We are installing tile floor and walls in our bathroom. In one area we have a span of 26 inches. (behind an access door for plumbing) My question is can we install the backer board over a 26" span and install 12" x 24" horizontal tiles on it? Or do we have to have the backer board screwed to 2 x 4's on 16" centers? Thanks in advance!

[Lili88]

To install the 12" x 24" horizontal tiles is a good desition, but the both variants will work.