Fair play. You said you're putting the bearers at right angles to the floor joists, any particular reason you chose to do that rather than have them parallel?
I'm not doing anything to he floor joists, they will come as part of the pre-made floor section/panel. I'm planning to run the bearers at right angles to those to minimise the contact area between the two (where moisture would be transferred).
Shedstore
From memory, the walls are 12mm thick T&G and the frame material is all 34mm x 34mm