I would like to build a 14'X 20' single story workshop at the rear of my home in Indiana. It would be very difficult to pour a traditional concrete foundation due to site access, tree roots, and wooden privacy fence.
Option 1:
Sink several 6x6 treated posts in holes filled with quick set concrete around the perimeter of the struture. Build a platform supported from these posts with conventional constructions from that point up.
Option 2:
Lay 20' long 6x6 treated posts on the ground evenly spaced on concrete pavers. Build a floor structure on top of the beams, then conventional construction from that point up. (possibly lay a thick piece of plastic sheeting on the ground between the wood and ground?)
The approx. distance from the top of the floor to the ground would be around 12-15"
Any advise or suggestions would be greatly appricated.