How thick did you make the pad? We are getting ready to put one in our new barn that we are building and was trying to get some info. I have been told 4'' but I dont know.
We used 2X6 boards for the frame and we put in a piece of metal panel to grip too and also a bunch of broken up pieces of concrete blocks and rocks to take up some room. So it is between 4 and 6 inches becasue of the 2 inch slop down to the drain and 6 inches at the edges.