There are many videos online of how to install Kerdi board and installation procedures are readily available on line where you will see that Kerdi board already has a waterproof membrane and you have to carefully tape all joints and holes.

@Jeff Meeks Yes, that's why I was a little confused. I read and saw different videos showing the contractors putting membrane on TOP of the kerdi. However, I was under the impression the kerdi was already waterproofed. Thanks for clarifying.

You dont tape the seams. You use NON modified thinset with Kerdi Band. at all board seams and corners inside/outside in the field you can use KERDI fix for the screw washers..

Any DIY tilers. Always stay ON the actual MFG (schluter) websites for facts.

Schluter is a bit anal about the "unmodified" thing. Overseas, they approve modified. Here, not so much. Truthfully, a morter like the lightly modified Versabond from Home Depot is just fine....

Also, with Kerdi Board, all one needs to do is use Kerdi Band on the verticals and the meeting of the Kerdi floor, walls and curb. The fasteners can be "flashed" with thinset or Kerdi Fix.....