(a) Single family residential dwellings, as defined in §388.002 of the Texas Health and Safety Code, that are newly constructed or reconstructed shall comply with §388 of the Health and Safety Code (Texas Building Energy Performance Standards).
(b) Effective September 1, 2016, the Texas State Energy Conservation Office adopted the 2015 International Residential Code (Chapter 11) as the state-mandated energy code for all residential construction, which includes one- and two-family residences of three stories or less above grade.

Source Note: The provisions of this §21.4 adopted to be effective January 2, 2022, 46 TexReg 9005