Here is the floor recipe of my personal project, the Hero Tomb.
As long as the floor is one of the most important art piece in a scene, I wanted to tackle it first to found the mood of my room.
It's still a WIP work where there is no blend, aging, patina, etc.. but there is the structura and main material repartition, all the rest is guilty pleasure, polishing.
For the materials my process is pretty simple, building bank materials and height map separately I then blend together. It allow me to speed up my process and keep constitency through all my materials and scene.
More process infos on my polycount Thread :)
http://polycount.com/discussion/185468/the-hero-tomb