Take a look at the attached. I was reviewing the 2010 California Plumbing Code, and I followed the formula they require. Static pressure - minus .5 per foot of elevation from highest fixture to the meter. The I looked at table 6-6, and matched it to the long run from meter to remote fixture, and my numbers come up at over 60 PSI, 80 ft run, and 39 fixture units. But as you can see, there are 3 options for 80 ft. and 39 FU's. How do I read this? I am re-piping with copper, and want to do it right. Thanks.