Texas State Energy Conservation Office adopts the 2009 IRC chapter 11
In June 2010, SECO officially adopted updates to both the commercial and residential energy codes in Texas. The new code for single-family homes is based on 2009 IRC, Chapter 11 (effective January 1, 2012) and the new code for other residential, commercial, and industrial buildings is based on 2009 IECC (effective March 1, 2011). Local ordinances can continue to adopt local amendments provided that the Energy Systems Laboratory (ESL) of Texas A&M University first reviews and accepts them.
The following is extracted from the SECO website