Washington, D.C’s Clean Energy DC Plan includes a recommendation for the city to establish a pathway for the phased adoption of net-zero energy building codes between 2020 (residential) and 2026 (commercial and multi-family). For the purposes of this commercial Energy Conservation Code, and prior to the time when the District adopts a mandatory net zero energy code for new construction, Appendix Z is intended to be a voluntary alternative pathway for project teams to comply with the code.