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Texas Building Codes: Improved Window Efficiency

Texas currently uses the 2015 International Residential Code (IRC) and the 2015 International Energy Conservation Code (IECC) for both residential and commercial construction. Per Texas House Bill 1736, on November 1, 2016, the 2015 IECC became effective for all construction in Texas other than single-family homes. And on September 1, 2016, the 2015 International Residential Code (IRC) became effective for one- and two-family homes and low-rise multifamily residential buildings in Texas. These codes bring about a number of significant changes for Texas:

  • According to the Texas A&M Energy Systems Laboratory, the update from the 2009 IRC to the 2015 IRC improves energy efficiency in residential buildings by approximately 10 to 23%, depending on the climate zone and the compliance option selected.1

  • Window efficiency requirements are improved significantly. The 2015 IECC requires an SHGC of 0.25 or lower for climate zones 2-3, and an SHGC of 0.40 or lower for climate zone 4.

For more information regarding the requirements of the 2015 IRC and IECC in Texas, please visit the Code Requirements section of our website. Click here for a two page guide to code requirements under the 2015 IECC.

1Texas A&M Energy Systems Laboratory Summary of the Laboratory's Stringency Comparison Analysis for Residential Provisions: TBEPS (based on Chapter 11, 2009 IRC & 2009 IECC vs. 2015 Codes, at D1 (November 2015).