The minimum state-mandated code for single-family homes is the 2015 IRC, Chapter 11 and the code for other residential, commercial, and industrial buildings is the 2015 IECC.
These codes are effective statewide, however, Texas is a “home rule” state allowing local jurisdictions to adopt amendments to the energy code. To amend the state code in non-attainment and affected counties, Energy Systems Laboratory (ESL) of Texas A&M University must first determine whether the amended code is as stringent as the existing state codes. Code changes that are determined to be as stringent or more stringent than state code may be adopted as local rule. Local jurisdictions are responsible for building energy code implementation and enforcement.