CITING CODE DOES NOT EXPAND THE SCOPE OF THE INSPECTION!
Building standards (codes) are created when experts in each trade get together and do their best to agree on what is safe. As they reach a consensus on each condition, they write it down as a building code "provision", finally numbering each one so that they can be found more easily.
When an inspector's comment is challenged, he can use the opinions of experts (expressed as a building code provision) to support his comment, or he can claim to be the expert in everything himself, which may not be accepted by a seller, their agent, or a contractor.
Just because an inspector refers to an expert opinion that supports his comment doesn't mean the scope of the inspection is expanded to include everything in the building code. The scope is typically defined in the agreement, often in the report introduction... and to 1st time buyers, maybe verbally.
BUT... THAT'S NOT ALWAYS TRUE!
If you inspect in N. Carolina, quoting code would mean you would have to comply with the following:
(a2) State Residential Building Code.
If a licensee includes a deficiency in the written report of a home inspection that is stated as a violation of the North Carolina State Residential Building Code, the licensee must do all of the following:
1. Determine the date of construction, renovation, and any subsequent installation or replacement of any system or component of the home.
2. Determine the Code in effect at the time of construction, renovation, and any subsequent installation or replacement of any system or component of the home.
3. Conduct the home inspection using the Code in effect at the time of the construction, renovation, and any subsequent installation or replacement of any system or component of the home.
In order to fully inform the client, if the licensee describes a deficiency as a violation of the Code in the written report, then the report shall include the information described in subdivision (1) of this subsection and photocopies of the relevant provisions of the Code used pursuant to subdivision (2) of this subsection to determine any violation stated in the report. The Board may adopt rules that are more restrictive on the use of the Code by home inspectors.
Like so many challenges that inspectors encounter, local conditions and regulations may apply and inspectors are responsible for understanding them.
I don't cite code provisions in my Narrative Library, but if a disagreement should arise, I wouldn't hesitate to cite one as support. Easy access to pretty much all building codes an inspector is likely to need are available on my website, and often provided in my templates, (depending on which software an inspector is using).