Barrier around shed base to hold dirt for retaining wall?

Question

Building a shed on a slope, and looking to add a retaining wall around it to block the space underneath, but offset the wall 2ft or so to add dirt and plants.

If possible, I want to be able to put something around the shed base to put the dirt up against on the back side of retaining wall without having to use concrete blocks. Keeping the space under the shed empty, and only filling dirt in between retaining wall and barrier. I am thinking of sealing the columns, and attaching wood wrapped in tyvek or something to protect it from rot.

The 6x6 posts, joists, and rim joists are all pressure treated wood.

What are some options to hold the dirt between the perimeter of the shed and retaining wall? Also do I have to leave a gap for airflow? Or can i seal it up to rim joist.

See picture for example.

Answer 1

You want air flow under the shed to keep it dry. The traditional barrier around houses on piers was a wood lattice, mostly aesthetic, and of course unwanted critters would get past it.

I don't understand your idea of a retaining wall and a barrier with a 2 ft gap. The purpose of this is not apparent to me; it sounds elaborate and a lot of trouble. My initial reaction is that Tyvek wrapped around wood in contact with soil would not protect the wood from rot.

Plants around a shed are going to lead to watering around the shed. I can see that just a lattice around the perimeter might seem stark, but there is a reason this was traditional. Whatever you do, leave some convenient access to put rat traps under the shed. If and when they are needed, put them in the special boxes to prevent pets or any non-target animals from being trapped.