Hattiesburg Climate Zone & Energy Code

Climate Zone: IECC Climate Zone 2A/3A (hot-humid, transitional). Hattiesburg's south Mississippi position produces hot, humid summers (96°F/77°F cooling design) and variable winters with occasional freezing events (27°F heating design).

Energy Code & Manual J Requirement: Mississippi State Building Code (IECC 2009). ACCA Manual J required for Forrest County and Lamar County HVAC permits.

Local Electric Utility: Entergy Mississippi

Building Department: City of Hattiesburg Community Development Department

Local Trade Association: ASHRAE Mississippi Chapter