When I built the house I wanted all my bathrooms, hallways and the kitchen floor to be tiled which was close to about 1500 square feet. The main floor is actually the second floor of the house so it's built from 3/4 inch tongue and groove plywood over 2 by 12 yellow pine resting on some steel beams because I have a 20 foot span over the Crawlspace where the Top Secret Tornado Bunker
is to be located then a 27 foot span for the bottom level which is a workshop, 3 car garage, storage room and bathroom. I was worried about tiling the kitchen mostly because it was such a high traffic area and a big span over nothing. The room is 14 by 27 with a large pantry and its sitting above the 3 car garage. You can't tile directly to the wood because the wood expands and contracts differently than mortar will so generally people use backer board which is like a 3 by 5 foot sheet of 1/2 thick masonry product and works very well but it's close to $10 a piece and I was gonna most likely need 170 sheets of the stuff.
I also worried what to do about the seams. I am sure they must want them taped and mudded before you tile them but I'm no expert and haven't researched it but I'd cover them with screen and mortar them just because.
I was worried about the seams expanding between sheets and maybe cracking the tiles plus its pretty dusty if you use a skill saw to cut it. You can use a razor blade which is fine if you just have to do a bunch of rectangular areas but it's a pain on a big job and another reason was as far as building funds were at the time, we were running on fumes so to save $1000 would be a big deal.
I googled a while and read about mudpans and then asked a few older builders I know, if they'd ever done any and was told that's how they used to do it so I thought a bit more about the fiberglass they put in concrete so you don't have to put down screen and my mortar mixer and the bounty of sand you can find in Florida and I came up with this method which hasn't shown any cracks or problems in the last 18 months or so that the floors have been down.