Originally Posted by theproffesor

Please explain the reason for placing the 2x6' flat. I dont get this. There stregth come from the vertical.

If they were vertical and elevated 6-10" high, supported by 4x4 risers every 48", placed on 16" centers, they would support a real car. So there is no need to worry about a tunmarsal tripibg and causing damage. The way you have it pictures there, there is almost no airflow under the floor. Of course moisture will be a problem. If elevated, then air could flow and moisture would be a non issue.

Please explain the structural engineering reason behind the method being used here. Or is this just another case of "thats what we saw someone else do"

But I do like how the edges between the osb are smoothed.