What changed in REScheck with IECC 2024?

REScheck Web added support for IECC 2024 in 2025, introducing stricter insulation requirements, tighter window U-factor limits, updated UA trade-off flexibility, and new Additional Efficiency Package Options under Section R408 and Appendix RG.

Do I need efficiency credits for REScheck under IECC 2024?

Many jurisdictions require Additional Efficiency Package Options when using the Component Performance Alternative. Section R408 typically requires at least 10 credits, while Appendix RG stretch code often requires 20 credits depending on local adoption.

Why does my REScheck pass the envelope but still fail compliance?

Under IECC 2024, passing the UA trade-off calculation alone may not complete compliance. Many jurisdictions also require efficiency credits selected from Table R408.2 before a REScheck report meets permit requirements.

Do all states use IECC 2024?

No. Some jurisdictions enforce IECC 2024, while others still use IECC 2021 or IECC 2018. Local amendments may also change requirements, so confirming the adopted energy code version with the building department is essential before submitting a REScheck report.

How many credits are required under Appendix RG?

Appendix RG stretch code typically requires 20 efficiency credits selected from Table R408.2, depending on jurisdiction adoption, climate zone, and project characteristics.

What is the fastest way to reach 20 credits in REScheck?

Many projects reach the required credit total by combining a high-efficiency HVAC system, a heat pump water heater, improved airtightness, and smart thermostat controls. Actual credit totals depend on climate zone, equipment specifications, and jurisdiction requirements.

Do all jurisdictions require Appendix RG credits under IECC 2024?

No. Not all jurisdictions require Appendix RG stretch code credits. Some enforce only Section R408, which typically requires about 10 efficiency credits, while others adopt Appendix RG, which typically requires 20 credits. Adoption varies by state and local building department.

What is the difference between R408 and Appendix RG in IECC 2024?

Section R408 requires selecting efficiency upgrades that typically total about 10 credits from Table R408.2, while Appendix RG is a stretch code pathway that usually requires about 20 credits. Whether Appendix RG applies depends on local jurisdiction adoption of the stretch code provisions.

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REScheck IECC 2024 Requirements: R408 Credits, Appendix RG & 2026 Compliance Changes

Mar 25
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Rescheck IECC 2024 Requirements

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REScheck IECC 2024 Requirements: R408 Credits, Appendix RG & 2026 Compliance Changes

Rescheck IECC 2024 Requirements

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(800) 671-1895 Ext. 702

brad@rescheckreview.com

Rescheck, Comcheck, and Manual J Reports

A Division of Certified Energy Raters, LLC WE Provide HERS MODELING and TESTING!

Rescheck IECC 2024 Requirements

A Division of Certified Energy Raters, LLC
WE Provide HERS MODELING and TESTING!