I am not sure the inspectors do that good of a job, lol... I never seen them inspect a ball valve with a glass eye, lol.. BUT what they do is keep the installer honest and up to code. I get 5-12 jobs a week inspected by local officials, they walk in, take a 5 minute look around and sign the permit, thats it, BUT knowing they are coming insures the contractor will install L grade copper where it belongs, low water controls where they belong, fire o matic safeties where they belong, Flue piping properly with enough clearance and proper terminations, ect... I have dealt with inspectors from NY, NH, CT, MA, RI, VT, NJ, TN, and FL and I can tell you in my experience they just look around and don't know much more than the highlighted codes, somce of the state commercial inspectors are on point but the local residential guys, just look around and sign the permit.. If they find something obvious they may catch it, but in most cases they don't even know what they are looking at lol {when it comes to the HE stuff like geo therm, hybrid, multi fuel, ect...
I can't count the times inspectors showed up before we were all finished and we pulled insulation by where a firomatic was supposed to be, or hadnt had any bx ran yet, and they never notice, we always do the job right but sometimes they are there before your done and don't want to wait for them to come back so you divert their attention a little and they walk right by...
That being said, there is still no substitute for hiring a contractor you trust... Its more the knowing the inspector is coming that gets the job done right than the actual inspection itself.... And there is also nothing better than a informed consumer, if you know the codes you will know that no corners are cut...
