Delaware Energy Code is reviewed by Delaware Energy Office every three years for potential updates to the most recent version of International Energy Conservation Code (IECC) and ASHRAE Standard 90.1.
Starting May 11, 2014 Delaware updated its energy code to 2012 IECC and ASHRAE 90.1-2010 with minor amendments. The code will be effective on Nov 11, 2014, after six months of grace period.
In 2004, the governor signed SB 306 adopting the 2000 International Energy Conservation Code (IECC) for residential construction and American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) Standard 90.1-1999 for commercial construction. SB 59, signed in July of 2009, strengthened Delaware's building code, requiring 2009 IECC for new detached one- and two-story family dwellings and all other new residential buildings three stories or less constructed after July 1, 2010. All other new construction built after July 1, 2010, including high-rise residential, must meet ASHRAE 90.1-2007. The bill further requires all new residential buildings constructed after December 31, 2025, and all new commercial buildings constructed after December 31, 2030 to be zero net energy capable. To be qualified as net zero energy capable, the building must be energy efficient enough that the building would consume zero energy if the building owner chose to install on-site generation.