Many people have been watching and waiting to see when Texas was going to adopt the 2009 energy code.  The state code ammendments went out for public comment back in April of 2009, and it was anticipated they might be adopted sometime early this year.  Well, the time is here.  On June 4, 2010, the state adopted the energy provisions of the 2009 International Residential Code (IRC) for single family homes and the 2009 International Energy Conservation Code (IECC) for all other buildings.  The changes, however, aren't scheduled to be implemented until April 2011 and January 2012. 

The ammended 34 Texas Administrative Code (TAC) §19.53 states:

(a) Single family residential construction.  Effective January 1, 2012, the energy efficiency provisions of the International Residential Code as they existed on May 1, 2009, are adopted as the energy code in this state for single-family residential construction... 

(b) All other residential, commercial, and industrial construction. Effective April 1, 2011, the International Energy Conservation Code as it existed on May 1, 2009, is adopted as the energy code for use in this state for all residential, commercial, and industrial construction that is not single-family residential construction under subsection (a) of this section.

The adopted building energy codes set a minimum standard statewide.  The excerpt in the Texas Register states that the State Energy Conservation Office (SECO) will be sending a letter to all local government entities making them aware of the building energy code update, and that the agency plans extensive training on the 2009 International Residential Code (IRC) for local building officials and builders during State fiscal year 2011.
 
For residential construction, some of the major changes include requirements for building envelope and duct air tightness, energy efficient lighting, and lower U-factors and Solar Heat Gain Coefficients (SHGC) for windows and glass doors.  For commercial construction, major changes include higher insulation R-values, higher efficiency HVAC systems, and demand-controlled ventilation in certain buildings.

For more information, see http://www.energycodes.gov/states/state_info.php?stateAB=TX.  Or see the adopted rule at http://www.sos.state.tx.us/texreg/pdf/backview/0604/0604adop.pdf.