I’m looking at engineering my first project in Arizona…using the IRC/IBC. It seems that the IRC is to be used if not engineering is provide and the IBC is for engineered projects. However, it seems that they have similar tables with minor variations. It just seems a little strange to do things this way.

Any insight is greatly appreciated! Nothing like learning a new code on a dead line…wish I knew this before I submitted my proposal…

i believe the distinction is irc is strictly for one and two family dwellings, ibc covers all other buildings.