"Darryl" wrote in message
oups.com...
However, a 20x20 section of the floor slopes down to an unused sump
pit. How do I level the floor to compensate for this slope? Do I
first nail the 2x4s to the sloping floor (a very slight slope) and then
somehow level the osb panels, or do I make the concrete level first
before attaching the 2x4s?

Neither. Make the two by fours level by adding shims between
them and the concrete floor? then add the osb panels as you
have on the finished portion.

lee