The ceiling is sloped in the shower so there are a few more corners but they are not 90 degrees. I'm not so much worried about the ceiling (it's not a steam shower but might as well just do the whole thing rather than deciding where to stop) but at the low side of the wall (above the bench) it's only about 5' off the floor so that should be carefully waterproofed as well. Does that require some kind of site fabricated geometrical nightmare corner?

This is probably the best pic I have, sorry.

The link's below for the online site to buy the Kerdi.

Concerning hanging the Kerdi vertically, it's 6 of one, half dozen of another. You can wrap the corners either way (horizontally or vertically) without Kerdiband. It just makes it MUCH easier to get the Kerdi snug into the corner, and KEEP IT THERE.

As for anything else, you might want to fir out the front of the bench so that the cement board doesn't "bulge" out at the bottom, and then when screwing the cement board in, spread a little loose thinset on that flange just to make sure there's no void there. (It'll squeeze i when you screw it down. Same with the rest of the walls. That's got to be the tallest flange I've ever heard of!

Here is a link that might be useful: tile-experts.com

Yes, all of the walls were furred out so that the cement board would sit inside the flange without bulging. I think the reason that the flange is so tall is that the base is flat. It's not "bowl-like" like most bases are where the sides of it come up a few inches and then there is a small little lip that you tile to. Of course it pitches to the drain. I'm not sure why it's so tall but once you have to fur out to miss the flange anyway it doesn't much matter. Their installation instructions do instruct you to fur out the walls though.

You can wrap the corners either way (horizontally or vertically) without Kerdiband. It just makes it MUCH easier to get the Kerdi snug into the corner, and KEEP IT THERE.

I'm confused. Are you saying that it's easier to NOT use the Kerdiband in the corners? I didn't use the Kerdiband, and felt that it was much more difficult trying to wrap the Kerdi into the corners. If I were doing it again I would definitely buy lots of Kerdiband!

No, I'm saying it's easier TO use the Kerdi-band. It can be done without it. but you have to be very careful when smoothing it out and squeezing out the excess thinset that you don't pull the membrane away from the corner (and it's very easy to do). It's much easier with the Kerdi'band, which is only 5-6" wide, to make sure it stays in place as you smooth it out, and then seam the sheets of Kerdi over it.

So you put the kerdi band in first and then cut the kerdi to fit short of the corner?

I find both ways (running Kerdi through a corner or using strips of Kerdi or Kerdi Band) equally easy. I showed both methods in that Kerdi Shower thread, often times what I use depend on the layout and where the seams will fall.

For this 36" by 65" shower, vertical will work. the Kerdi is 1 meter wide, about 39-1/2" or so.

On your long wall, 65" divided by 2 is 32-1/2", if you do a 2" overlap in the middle of that long wall that leaves you with an extra 5" of Kerdi to run through each corner. Or a little more overlap (3") in the center will net you a little less running through the corner (4").

I buy through tile-experts.com and tileprotection.com

For the wacky neo-angle corner, wrap the material over on itself as tight as you can and if you're really concerned, put a dab of Kerdi Fix on it. Use a pair of scissors and a piece of paper to get a size, cut locations, and folds that will work, then transfer that to a piece of Kerdi.

For the corner pieces you want for your bench, if you're using a Kerdi Drain, often times a few corner pieces are included in the drain package. Ask your seller. Some sellers have been known to remove the corner pieces and resell them separately.

Mongo

I need to revisit the mongo kerdi thread, I thought that you did not use kerdi band but the memory isn't what it used to be.

No kerdi drain here.

I didn't use Kerdi Band, but on one of the corners I used regular Kerdi that was cut into a strip, and set is as if it were Kerdi Band.

Thanks Bill, I thought that was probably what you meant, just wanted to clarify.

I'm "Mongo".

"Bill" is the smart one.

Mongo

She WAS talking to me. :-) I clarified an answer for her earlier.

See what I mean?

You are the smart one!

Mongo

I was thinkin it, buuuut I wasn't gonna say it!! :-)