RR, This is what I was taught where I went to school. But, as you said “in today’s world” I guess education is not part of it. !!
My father had to work as a journeyman before he could be a contractor. Like the OJT requirements so many of us are opposing in this profession.
“one profession rarely knows what the other profession is doing”
That is what the lead construction supervisor is there for.?
That is what the “General Contractor” is "supposed to control.
By “around that pipe,” I mean that the HVAC contractor should not allow anything to pass through his duct. There IS something wrong with “going around”. Every 45-90 degree fitting has pressure drop that must be calculated into the duct design. Before I do any of that design, I’d just pull out my sawz-all and get it out of the way.
“You’ve got a lot of educating to do with those other professions, then, apparently.”
As I posted, the education is the responsibility of the general contractor not the individual sub-contractors.
Just because it is done that way all the time is not reason to assume it is OK. However, I feel that as a home inspector, there is no reason to try to change the world. For example, putting two or more natural wires under the same buss bar terminal screw is not right, but is done in 99% of new construction. Until I can show that there is a definite deficiency (overheated circuit ect…), all I do is state the facts as I saw them. I do not call in a sparky to repair it. If there is a gas pipe through the return duct/plenum and there is no fitting to leak, and that the duct is sealed around the pipe and Radon Testing shows no elevated Radon levels being drawn into the duct and distributed throughout the house, than I’s say just report the pipe in there and go about your business.