In April 2026, the State of Delaware Division of Climate, Coastal and Energy Office amended the Regulations by adopting the 2024 International Energy Conservation Code and the ASHRAE 90.1-2022 for commercial and high-rise residential buildings. This regulation also adopts Appendix RE: EV Charging Infrastructure and Appendix CB: Solar-Ready Zone with amendments to align with corresponding statutory requirements.
Effective January 1, 2027, Sussex County will require all new homes, conditioned residential additions/accessory structures and commercial buildings to comply with the 2024 International Energy Conservation Code as adopted.
All new homes, conditioned residential additions/accessory structures and commercial building plans submitted to Sussex County after December 31, 2026, must be designed to the 2024 IECC and have an energy compliance worksheet such as a “REScheck” or “COMcheck” accompanying all plans.
For more details, you may contact the Delaware Division of Climate, Coastal and Energy Office on their web site at: https://dnrec.alpha.delaware.gov/climate-coastal-energy/efficiency/building-energy-codes/
Any questions regarding these requirements, may be directed to the Sussex County Building Code Office at (302) 855-7860 or awright@sussexcountyde.gov.