Last year I erected a 7x7 Rubbermaid tool shed. I realize your structure would be larger and heavier, but maybe this will help. You want a rigid floor that will not become wavy. What I did was to first level the soil without disturbing it too much. Then I laid down about 4 inches of crushed stone surrounded by a frame of treated 4x4s to keep the stone confined. The frame was anchored with 2 ft pieces of rebar driven through 1/2" holes in the 4x4s. This area of crushed stone was slightly larger than the footprint of the shed. Stone was then tamped with a hand tamper. Of course everything was leveled. On this bed of crushed stone, I put a frame of treated 4x4s the size of the shed. I then installed joists, about 16" on center, of treated 2x4s, which I anchored to the frame with galvanized metal brackets. I then used 1x6 deck flooring for the floor. After a year and a half, with a lot of weight on the floor, it shows no sign of sagging. Hope this helps.

Just use normal wood decking —————————————————— (Wood cedar / treated) Pros Easier to repair -Can refinish to a different color at a later date -Has options for hidden fastener (camo is the name I think) -Stain or paint yourself/ contractor so no issues with finish -Cheaper than “composite” decking even if you decide to do cedar -Has a warranty Cons -Can rot, split, warp -Maintenance restaining or sealing —————————————————— (Composite decking “Ultradeck”) Pros -according to menards should not split crack or warp (seems like it does do this a lot though) -pre finished -Has a warranty Cons -Expensive -Often has issues with finish -Hard/ impossible to touch up if decking gets scratched or scraped -Often cracks splits warps (sometimes issue gets resolved) -Will fade (Color will fade in first month) which makes a replacement board look a different color down the road -Wood based composite up to 50% real wood —————————————————— Feel free to add any other pros or cons you think missed

Well, years ago I laid down cedar 2x6's and put a 5/4 cedar deck down over a covered roof/deck. Did this in sections so at any time they could be lifted and the roof cleaned underneath. I since moved away but have been back and ten years later everything is peachy keen.

spanky, I built a floating 25x30 deck for my kids to play hoops on. I built it two years ago and it has worked out well. The only issue thus far is inconsistent frost heave. I live in northern MN, and the area beneath the deck does not have the benefit of snow insulation--thus, the frost penetrates the ground deeper. The deck gets lifted off some of the footings (primarily the perimeter footings, as they heave the least). In the spring the deck drops back down to its normal position.