Keep looking. Length must be evenly divisible by the width.

What is the application for the tile? I think you mean herringbone though.

the application is shower wall

The length does not to be evenly divisible by the width. What do you mean by basket weave pattern? There are several variations of it.

Yes, the length DOES need to be evenly divisible by the width, or the points will wander off course.

Illustrating the above point:

Source

And, a long skinny tile like that is more likely to suffer from warping, and you could end up with lippage. Check for flatness by putting two tiles together back-to-back and see if you can see any daylight between them.

IMO the wrong tile for either layout. IMO shower walls work best with as few a gout lines as possible and I often do the bathroom floor and shower walls with the same porcelain tile in 12 x24 to keep it simple, And yes the tile needs to be the right size too as stated above. BTW it is also more expensive to have either of those patterns installed.

The points will only wander off course in a herringbone pattern if the tile is laid incorrectly. It doesn't matter a whit what the dimensions are, as long as all the tiles are the same size. Don't believe it? Draw it out on graph paper.

The above diagram is one variation of basketweave. There are others that use 2 sizes of tiles. Are you sure the 12" dimension is really 12", though?

This is what you want. If the planks aren’t mathematically divisible, the points wander off of straight center. Wandering herringbone looks like, well, poop.

https://www.mannington.com/residential/hardwood/-/media/61788D441B5549BFB081919776BA50D9.ashx

Thanks for all the useful comments. We plan on having the tile professionally installed, but I'm leaning toward changing to the 6x24 tiles in a horizontal herringbone pattern. Only the back wall of the shower will be this pattern, and I believe this size tile can work because the 6x24 tile sides are evenly divisible. Here's an example of the pattern.

Bathroom Oak St · More Info

The side walls will be plain white, large format, and the feature tile is a slate look.

Check for flatness. Lippage is very apparent in showers because of the downlighting.

6 x 24 will work, as would 6 x 23 or 6 x 21, etc.

The diagram above shows how the points line up. They will also line up if every tile is 1" longer, or 1.74567" longer, or any length, as long as they are all the same.

Oh, well, you can lead a horse to water...

But please stop spreading misinformation.

catbuilder-

I agree with you. I think the main issue with getting the points to line up vertically for herringbone is that the installer is dead on with them being at 45 degrees. I had the same thoughts as you about people insisting that the tiles be some certain proportionate dimensions, because any rectangular tiles should work as long as they were all uniform in dimension, whatever those dimensions are. Even with tiles where the ratio of the long edge to the short edge is an exact multiple, you end up with ratio being slightly off once you add in the size of the grout line. For example, if you used a 3" X 6" tile with a 1/8" grout line, the tile effectively measures 3-1/8" X 6-1/8", and this is not exactly a 1 : 2 ratio: it's about 1 : 1.96.