Wow Thanks Guys! I did search for those discussions on air lines but I guess I need to improve on my searching skills, Kinda new to forums, (sorry) However you folks are fantastic! I really appreciate all those responses.
As to the load placement on the floors that was already factored in prior to construction. I have a very sturdy floor.
I am putting OSB on the walls and I am leaving the ceiling open. I built a 2 bed room apartment above the shop so having the 2nd floor joist open allows be to add and electric or anything else to either floor at any time.
Air lines, I was pretty much set on Iron pipe anyway, I was worried about breaking at the joints. Copper is nuts now in todays market. I really like copper but gave in to CPVC for water supply lines on this job because of price. I am starting a new house next spring 09 and I will be switching to Pex.
I can see already that I wont be doing much without consulting here first. You folks are supper knowledgeable! Thanks!