How can I mitigate water contact with a 2x4 screwed into concrete floor?
Looking at Mattias' article on woodgears.ca, I think you can hang the uprights from the overhead floor joists and cut them off above the floor.
The 2x4s coming down the wall provide a method to affix the shelving unit to the wall, not provide support from the floor. Some of the other contributors have &quot;half-height&quot; shelves pictured that only come down the wall so far.
You could probably still do it by &quot;hanging&quot; the uprights from the ceiling, but I don't know that it can support as much weight as installing it as designed.