HOW do you take a toliet up, and fix the floor before it falls in .
Before you do anything make sure you turn off the water! That's the dial looking thing behind the toilet on the water line. You might want to have some rags or towels close by you when you start your project...anyway undo the screws located on either side of the bowl, on the floor portion of the toilet and pull. You'll probably want to replace the wax seal (they're cheap) when you replace the bowl. Hope this helps. To fix the floor you'll probably need plywood. I hope you replace everything that is mouldy or rotten! And I hope you have some power tools to make your job faster and easier.
Taking the toilet up is the easy part. There should be two bolts on the sides of the base that have to come loose. A lot of the time these are rusted or corroded so badly that you have to use a hacksaw to cut them off. You'll need to cut the rotten part of the floor out to the center of the floor joists that are past where the rot stops. In the space between the joists it's a good idea to install a piece of lumber the same size as the joists between them so that the end of the new piece of plywood is sitting on something. Position the new piece so that it will be half under the old plywood so that it will support both the old and new pieces. Basically you want a square frame to hold up the new piece of floor you'll be putting down. The biggest problem is usually that since the toilet sits so close to the wall that sometimes the water damage extends underneath the wall. If that's the case, then I'd suggest calling in someone with experience. If not, then cut a piece of 3/4 inch plywood to fit the hole that you cut out. If you're putting linoleum of something soft down for the floor, then use wood putty to fill the gap between the old and the new sub-floor otherwise you'll be able to see where the gap is because the flooring will eventually sink into the gap. If you're doing tile, you shouldn't have to worry about it.
be sure to take the time to frame in the toilet
