The goal of my last column was to begin to change the way most plumbers size natural gas distribution systems. In my experience most plumbers, and even Authorities Having Jurisdiction size natural gas systems based on the example in the Uniform Plumbing Code where the Btus/ft3 is shown as 1,100 (2015 UPC Figure 1216.1.1).
Before I get into the thick of things, here are a couple things to be aware of that others might question on any value used for Btus/ft3: