2021 International Energy Conservation Code – IECC-2021

The 2021 International Energy Conservation Code® (IECC) sets the baseline for energy-efficient design and construction of new buildings, as well as additions and alterations to existing residential and commercial structures. It features separate residential and commercial provisions and is fully integrated with the 2021 I-Codes for coordinated compliance.

Highlights:

• Divides content into Residential (≤3 stories) and Commercial sections for targeted regulation
• Includes multiple compliance paths: prescriptive, performance-based, and Energy Rating Index (ERI)
• Updated climate zone data affects insulation and system efficiency by region
• New requirements for air barriers, insulation materials, and fenestration U-factor/SHGC
• Enhanced HVAC efficiency standards and ventilation control requirements
• Revised lighting power limits, daylighting controls, and sensor use for commercial spaces
• Strengthened water heating system insulation and controls for energy savings
• Specific provisions for renovations, historic buildings, and changes in use
• Expanded commissioning requirements and documentation protocols
• Optional appendices for solar-ready design and zero energy building frameworks

Who It’s For:
Architects, energy consultants, engineers, and code officials seeking to meet energy efficiency standards for code-compliant, sustainable buildings.

IECC-2021