The middle section sub floor was the easiest area to remove. Without the curve of the end-caps to deal with, and about a 3rd of the amount of bolts to cut through, it was, by far, the easiest section.
Since we didn’t have to preserve any of the floor like withe end-caps, I could simply set the proper depth on the circular saw, and cut a path along the edge against the wall.
At that point the only thing holding the floor down was the screws through the subfloor into the steel frame.
Over the course of removing the subfloor we tried many different methods for removing those screws. In the end, the simplest method was also the most effective. We simply used the circular saw to cut a square around each screw, then lifted the now detached subfloor up around the cuts. Leaving “islands” of wood surrounding the rusted screws in the steel frame.
Those little island of leftover wood and screws can easily be removed by chiseling away the leftover wood and, and using pliers to unscrew the stripped and rusted screws from the steel frame.
As with every other piece of subfloor, we found mice droppings and occasionally a carcass. You never know what kind of diseases will hang around mouse droppings, even old ones, so it’s best to be safe and squirt them down with bleach before cleaning them up. If you don’t wet them with bleach first, sweeping or vacuuming them up may put contaminates in the air that can be inhaled.
The only tricky part of demoing this section of subfloor was the toilet ring. This hard, plastic ring overlapped both the black water tank under the floor, and the subfloor itself.
We didn’t want to damage the black water tank in anyway, so initially I tried to wiggle it free of the tank by flexing the ring with a crowbar. The plastic was too stiff, and the overlapping lip of the ring was too big for it to come of that way, so we had to cut it off.
I used our little Ryobi multi-tool with a saw blade attachment to cut off the top lip of the toilet ring, making sure not to cut any of the black water tank’s rim.