I must say both have there benefit & are practical but even though the U.P.C. is at most times more demanding/detailed/exacting I personally LOVE the I.P.C... Why??? Only because it has absolutely "CHANGED MY LIFE FOR THE BETTER"... So I just adhore it also the I.M.C. (International Mechanical Code)"Love it", & the I.F.G.C. (International Fuel Gas Code)"Love it"... These very books issued by the I.C.C. (International Code Council "Love them") & test/exams that they (the I.C.C.) publish compliments in its greatest fashion the authenticity/legitimacy of a true tradesmen(if administered correctly). For example I have all 3 of my Master License's = "National Standard"(Master Plumber License, Master Mechanical License, Master Gas Pipefitter License & not to mention the National Building Contractors License type(A)) these license's have propelled be in a direction of forward & now these very license's "Commands Respect"... What's your thought's???