Large Scale Central

Storage Shed

I like the way Richard Smith constructed his storage shed. I have been thinking of such a shed for over a year. Has anyone built a shed like this using a concrete floor and a regular metal roof? I have a water shed problem coming down where the shed will be. I never know if I will have inches of snow or several feet of snow up hill from the shed. I have considered building a 2-4 inch concrete wall on top of the concrete floor before the wood sill and a floor that drains down hill to the doors with a 2 or 3 inch drop in 10-16ft but the cars might roll on metal track.
Then there is the use of used metal roofing. Any problems using this? Yes drilling metal and weight maybe.
What about security having 1,000s of dollars of rolling stock out doors. If Hasped and clocked will a thin wall or roof give easy acess to the trains.
Can the water and theft problem be resolved?
Frank barnard