We're in the process of building a custom shower bench in our new shower and were curious on the options/process we have.

The bench will be outside a prefabricated swanstone shower pan. I know it has to be waterproofed etc before we can tile it but was wondering that material we should use to waterproof it.

Any help would be appreciated.:D

This is sort of complicated. I suggest you try the John Bridge forums for detailed advice.