2025 NGBS Interpretation: 902.2 Whole Building Ventilation System

Published Tuesday, June 9, 2026

Home Innovation has determined that testing is not required to comply with Practices 902.2 or 11.902.2 when a project demonstrates compliance through the ventilation provisions of the 2021 International Residential Code (IRC). While the IRC contains ventilation testing requirements, those provisions are located within the Energy Conservation chapter rather than the Mechanical chapter referenced by the NGBS, creating ambiguity as to their applicability. Based on the development history of the 2025 NGBS, the structure of other NGBS practices that separately identify testing requirements, and the fact that ventilation testing is addressed elsewhere in the standard (e.g., Practice 902.2.2 for exhaust airflow testing), Home Innovation concluded that IRC ventilation testing was not intended to be a condition of compliance with Practices 902.2 or 11.902.2.

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