Okay... I've got the Hardibacker mortared and screwed down on my kitchen floor and I've got my tile layout planned and I'm picking up a tile saw today... essentially, I'm ready to start laying tile.
However, I was googling tile projects for a little refresher and I read somewhere that if you're planning on using a light colored grout, you should use light colored mortar to adhere the tiles... and conversely you should use dark mortar with dark grout.
I've always thought grout was pretty much opaque... does this really matter?
The reason I ask is, I've got a bag of dark gray mortar and I was planning on using sort of a natural medium gray colored grout on my floor. So, I suppose I could go either way light or dark?
The color of the thinset does NOT matter when installing anything except some marbles or translucent stones such as Onyx. You clean any thinset that oozes up as you set the tiles and go back to remove any you've missed. The top 2/3 of the tile thickness is for grout.
What you read should have read that you can "use white with light and gray with dark" with the thought that if a little shows, it won't be as noticeable. But that doesn't work either, white thinset is NOT like white grout, the same for grays.
TILE GUY - retired- TROY, MI - Method & Product suitability consulting.