you could have him tape off the black seam and fill in the white with white grout. Allow it to dry, tape off the white seam and fill in the black with black grout. Then you won't mess up the pattern.
dash,,, these are cement tiles, yes? (not porcelain?) Your tile guy who is grouting has to be very careful using dark grout. Have the tiles been sealed? That's a must prior to grouting.
**do not let the sealer drip down the sides**
Also, he can't grout this floor like he would other tile floors (spreading the grout all over the tiles and using a float to push it in the joints). The dark grout will stain the tile. yes, even if sealed it will stain it. To grout w/dark grout, you basically have to pipe it in the joints and quickly clean off any residue. Even the tile manufacturer will tell you the same thing. (they actually advise against using black or dark grout just for this reason)
Do NOT let him spread the dark grout all over the surface of the tiles.
The charcoal or black is the correct color for the grout. I wouldn't do white or gray.
I did mine w/black and even though I was very careful, I got some staining on the edges. I sealed these 3 times before they even went on the wall. If water beads up on the surface of your tile, it's properly sealed. If it doesn't or the tile absorbs the water, NOT sealed.
If you zoom in on this pic you can see the slight dark staining on the rough edges of the grout line. it's unavoidable. Your tiles seem to have a smoother edge than mine did, so you may not have this problem
Yes it's possible. I've certainly combined grout colors taping off. The OP's patterned tile would be a nightmare. Combining white and black grout is as bad as it gets. Let's entertain the idea for a moment. Would it not be easier to grout it all one color and grout stain the second color. Just a thought.
you could have him tape off the black seam and fill in the white with white grout. Allow it to dry, tape off the white seam and fill in the black with black grout. Then you won't mess up the pattern.
dash,,, these are cement tiles, yes? (not porcelain?) Your tile guy who is grouting has to be very careful using dark grout. Have the tiles been sealed? That's a must prior to grouting.
**do not let the sealer drip down the sides**
Also, he can't grout this floor like he would other tile floors (spreading the grout all over the tiles and using a float to push it in the joints). The dark grout will stain the tile. yes, even if sealed it will stain it. To grout w/dark grout, you basically have to pipe it in the joints and quickly clean off any residue. Even the tile manufacturer will tell you the same thing. (they actually advise against using black or dark grout just for this reason)
Do NOT let him spread the dark grout all over the surface of the tiles.
The charcoal or black is the correct color for the grout. I wouldn't do white or gray.
I did mine w/black and even though I was very careful, I got some staining on the edges. I sealed these 3 times before they even went on the wall. If water beads up on the surface of your tile, it's properly sealed. If it doesn't or the tile absorbs the water, NOT sealed.
If you zoom in on this pic you can see the slight dark staining on the rough edges of the grout line. it's unavoidable. Your tiles seem to have a smoother edge than mine did, so you may not have this problem
Yes it's possible. I've certainly combined grout colors taping off. The OP's patterned tile would be a nightmare. Combining white and black grout is as bad as it gets. Let's entertain the idea for a moment. Would it not be easier to grout it all one color and grout stain the second color. Just a thought.