City of Houston - Residential and Commercial Green Building Requirements

Residential

In 2014, the City Council of Houston passed Ordinance No. 2014-5, requiring new residential construction to exceed the energy efficiency requirements under the 2009 International Energy Conservation Code (IECC) by 15%. In October 2016, the City of Houston adopted Chapter 11 of the 2015 IECC with amendments per state law.

In October 2023, the city adopted the 2021 IECC with amendments. Houston adopted Appendix RB of the 2021 IECC, the Solar-Ready Provisions -- Detached One- and Two-Family Dwellings and Townhouses, with a minor technical amendment as a mandatory standard.

It also adopted Appendix RD, the Electric Vehicle "EV" Ready Residential Provisions, with amendments as an optional standard. The EV provisions apply to single-family dwellings, two-family dwellings, and townhouses. Each dwelling unit with designated onsite private parking must have at least one EV Ready space. "EV Ready" is defined as an automobile parking space with a branch circuit and either an outlet, junction box, or receptacle that will support an installed electric vehicle supply equipment (EVSE).

Commercial

In April 2008, Houston adopted the City of Houston Commercial Energy Conservation Code based on ANSI/ASHRAE/IESNA Standard 90.1-2004. In December 2016, the City of Houston adopted the 2015 IECC with amendments per state law and ASHRAE 90.1-2013 with amendments.

In October 2023, the city adopted the 2021 IECC with amendments. Houston adopted Appendix CB of the 2021 IECC, the Solar-Ready Zone -- Commercial provisions, in full as an optional standard. It also adopted Appendix CD, the Electric Vehicle "EV" Ready Commercial Provisions, with amendments as an optional standard. The EV provisions apply to multi-family residential and commercial buildings. New parking facilities with at least 10 parking spaces must have installed EVSE, EV Ready spaces, and EV Capable spaces. The amount of each is determined by the type of building. Additional installed EVSE spaces can be used to replace EV Ready and EV Capable spaces, while additional EV Ready spaces can be used to replace EV Capable spaces.

Installed EVSE must have a minimum charging rate of 6.2 kilo volt-amperes or 30 amperes at 208/240 volts. "EV Ready" is defined as a designated parking space with a dedicated branch circuit with at least 40 amperes and 208/240 volts that terminates in a junction box within 3 feet of the parking space. "EV Capable" is defined as a dedicated parking space with electrical panel capacity and space for a branch circuit with at least 40 amperes and 208/240 volts, and is equipped with underground and surface-mounted raceways, to enable the future installation of EVSE. A single branch circuit is permitted for two adjacent EV Ready or EV Capable spaces.