Shed floor damp/draught sealing and treating questions?

scudster

A bit of background first before I ask you good people for some advise.
I've just built myself a 10ft x 10ft garden shed from scratch to house my motorbike and tools and to use as a mini workshop/mancave. I live in a rented house so it's constructed in such a way that each wall/roof section simply bolts together if I ever move house (flatpack design) and in each corner I have adjustible threaded feet to level it and keep the whole shed off the ground (cant lay a concrete base due to rented house and can only have the shed situated on a lawn). The frame is constructed from 50mm box section and clad with reclaimed 80mm box profile insulated panels to help prevent condensation. I have purchaced secondhand scaffolding planks to floor the shed and these will sit on the 50mm box section frame and cross members.

My first question is how should I go about sealing underneath my planks to prevent damp ingress and reduce heat loss/draughts?

Second, what wood treatment/preserver should I apply to my planks to keep them in good nick?

genuine leather

Hey scudster
The fact that its a temp structure, i d be inclined to fit a 1000/1200 guage plastic to the top of your cross beams first and turned up the sides maybe 6 inches, then i would lay sheets of 50mm rigid insulation(3/4 sheets needed depending on span of beams,and centered over each)on top of that lay 3/4 sheets of 12 mm plywood and lay down your planks on top of that. the ply would protect the planks from damaging the insulation.
i feel there would be no need for wood preserve as they are protected from the damp underneath. Just my two pence worth
Hope this helps
GL