Reinstating shed foundation

by Edwin
(Waldorf, Maryland)

I have removed the foundation and floor of a 25 yr old 12' x 20' shed that was built with 4x4 skids set on the ground and 2x4 used as floor, end and rim joists. All the materials were totally rotted from moisture. The ground was still wet and muddy. The original builder did not prepare the ground for this eventuality.

My question is this; What can be done at this stage to prevent this same thing from happening again? The basic framework is in good condition. It was discovered that the shed had sunk into the ground 4".

I have raised the framework to its original height and it is now being supported on all corners with rafter supports. Recently we had a couple of weeks of rain and the ground beneath the shed was completely covered with water.

Help!
Any recommendations? Is this a lost cause?

I want to use treated 4x4's for the foundation of a 12'x20' Shed. Do I place them directly on the ground or spread sand, gravel or crushed rock on the ground first before laying the 4x4's down?

Best regards

Ed