Housing codes are adopted at the municipal or state level. There is no mandatory "national" building code in the U.S., though there is a "model" building code at the national level upon which the state and local building codes are based. (https://localhousingsolutions.org/housing-policy-library/hou...)

Specifically, Texas just uses the ICC's IRC, while California has the California Building Standards Code, which has additional requirements to account for our many earthquakes (https://peer.berkeley.edu/sites/default/files/peer2019-05_ss...).