Hartford Climate Zone & Energy Code

Climate Zone: IECC Climate Zone 5A (cold-humid). Hartford's inland Connecticut location produces cold winters (7°F heating design), hot and humid summers (90°F/73°F cooling design), and meaningful latent loads during the summer season.

Energy Code & Manual J Requirement: Connecticut State Building Code (2021 edition, based on IECC 2021). ACCA Manual J required for residential HVAC permits. Connecticut's clean energy programs (Energize Connecticut) provide incentives for high-efficiency heat pumps that align with accurate Manual J/S sizing.

Local Electric Utility: Eversource Energy (Connecticut Light & Power)

Building Department: City of Hartford Building Department

Local Trade Association: ACCA New England / ASHRAE Connecticut Chapter