90 degree herringbone grout line issue

[Demand]

I’m trying to do square (straight) herringbone with a 4x12 tile. I’m not getting the math on how you can do it if you add grout lines to horizontally laid tiles. If I add 1/8 line the width becomes 4 1/8 and 3 tiles horizontally are now 12 1/4. I see examples on the web but no one mentions how to handle the extra width. Any help is appreciated.

 

[Jimbob12]

The short length side of the the tile has to fit perfectly along the long length side of the tile perfectly for herringbone to work. If it doesn't ( grout joint included ) then herringbone isnt possible.

 

[Demand]

thanks. It’s that simple for me too, now trying convince my wife it won’t work. She’s now trying to convince me to do a traditional herringbone which I explained is the same thing just turned to a 45.

 

[Slippery]

Is it not because the Herring bone, once laid would have a 45 deg angle, not a straight tile edge at the margin?

 

[Slippery]

 

[Chris Metcalfe]

I've come across this very problem on my current job which is the first time I've attempted herringbone. My tiles are 200 x 100 (exactly). I've been pulling my hair out for several weeks now. I did manage to devise an extremely convoluted system to do it however it's been a nightmare and one I won't be repeating. I've been using a combination of 2mm and 3mm spacers. Horror. What can I say, it was too late to turn back. Would I be right in saying then that the correct tile size would be for example 202mm x 100mm, for a 2mm grout line?