In standard poured shower pan construction there is normally a rubber layer between the bottom flat layer, and the upper sloped layer.
Today I came across the following "updated" method:
(credit: Mr. Money Mustache)
I am under the impression that redgaurd is used primarily to keep splashes and overflow from causing an issue, and not as a primary water repellant.
Is redgard, or any comparable product, able to hold up under this kind of abuse?
Yes that is what RedGard is for (I assume you are planning to tile over the top of it). It is a waterproof membrane, it stops any water that might make it through the cracks in the tile (or grout). It is not intended to stand up to the abuse of a normal shower wall or floor so it must be covered with tile.
From the company's website:
Rated for extra heavy duty service
Meets Uniform Plumbing Code specifications for use as a shower pan liner
I used RedGard to waterpoof behind my tiles in my tub surround. It was pretty easy to work with.
