A hidden floor and buckled boards

So it was back to more work and in doing some research for the next stage of the conversion we discovered a hidden floor in one of the proposed bathrooms which, when the first floor is removed will give us, an extra foot of head room give or take and inch or two, that 30cm in new money. You can see I have uncovered the frame work for the false floor. The bad news is that we will have to replace the floor joists before we can install the bathroom because the existing ones are not strong enough. This room was part of the farm buildings and it was probably used to store hay or something similar and so the joists did not need to be that strong. I also had to remove all the insulated plasterboard that the previous owners had installed as it had all buckled and bowed so no chance of sticking tiles on it. below the first picture is the stripped out room waiting to have the final floor boards removed so we can install new joists, we won't remove this until we have cleared out the room below. I 've done this work slightly out of order as this is not the next room to be tackled, or even the one after, but since the weather was so poor I needed to do some work inside.