The Rule

ASHRAE 90.1 sets minimum energy-efficiency requirements for buildings and includes provisions that require energy recovery in ventilation systems above certain airflow and climate thresholds.

Why It Matters

• Many US jurisdictions adopt 90.1 as code
• Compliance often forces a recovery device
• It pairs with AHRI 1060 for rated performance

Practical Effect

If your design exceeds the threshold, you must show recovery meeting the standard - which means selecting a device with a credible rated effectiveness and documenting it.

Tip

Check the edition adopted in your jurisdiction; thresholds and exceptions change between versions.