Re: The difference
Brudgers,
"when there are two or more possible code interpretations the most restrictive code interpretation does not necessarily apply."
You bring up an important and often misunderstood subject.
Both 104.1 of the IBC and IRC;
"The Building Official shall have the authority to render interpretations of this code and to adopt policies and procedures in order to clarify the application of it's provisions."
Many people think that to interpret; you give your opinion, or view. That is not true.
Merriam-Webster Dictionary; Definition of Interpret.
"1 : to explain or tell the meaning of : present in understandable terms."
Merriam-Webster Thesaurus; Synonym of Interpret.
"Meaning: to make plain or understandable."
Explain
There is only one authoritative "Interpretation" of the codes according to the code book; and that is the Building Official's.
The purpose of interpretation is to explain a code requirement to someone who does not understand.
As an inspector; if a contractor asked me about a code requirement; I would tell them what I knew and if they didn't understand that; I pulled out my code book (always have a copy in the truck) and showed him/her the code section. If they did not understand the words; then they could ask the Building Official to explain it to them. And, yes, sometimes when we read the code section together; I found out that I was dead wrong.
(By the way; when I first started doing the above; they were surprised; but, as time went on and they saw that I was willing to share; not only what I knew; but, also show them the code section; they were much more trusting in me and often asked to see code sections that had nothing to do with the inspection.)
The codes are not theories that are subject to differences of opinions. They are factual statements.
ps. My favorite word in the code books is "shall".
Uncle Bob