Do I use IRC or IBC?
FAQ-IRC-VS-IBC · faq
1–2 family dwellings and qualifying townhouses: IRC 2021. Apartments and commercial: IBC 2021.
New house, addition, garage, deck, or basement finish on a one- or two-family dwelling → IRC 2021. Townhouses → IRC if they meet the IRC townhouse definition; otherwise IBC. Multifamily apartments and commercial → IBC. Electrical still follows NEC 2020 with Ava’s #12 AWG minimum.
Not legal advice. Confirm against the City Clerk’s official copy before issuing a permit or citing a violation.