WHMV can be provided through four common styles: exhaust only, supply only, central fan integrated supply (CFIS) (a form of supply only), and balanced, which include energy recovery ventilators (ERV) or heat recovery ventilators (HRV). Poor design of the WHMV is one of many common causes of inadequate ventilation.Įnergy conservation efforts have resulted in tighter homes with better control over air leakage, which has led to reduced natural ventilation to the point where WHMV is needed to ensure adequate indoor air quality. Several studies in different parts of the country have consistently shown that many homes with WHMV systems fail to deliver adequate ventilation ( Sonne et al. Verifying the delivery of adequate ventilation in a whole-house mechanical ventilation (WHMV) system is critical to the function of the WHMV system as well as the health of the building occupants. See the Compliance Tab for related codes and standards, and criteria to meet national programs such as ENERGY STAR, DOE’s Zero Energy Ready Home program, and EPA’s Indoor airPLUS. To see test standard ANSI/RESNET/ICC 380-2019, which covers whole-house mechanical ventilation airflow measurement methods, see the Standard for Testing Airtightness of Building, Dwelling Unit, and Sleeping Unit Enclosures Airtightness of Heating and Cooling Air Distribution Systems and Airflow of Mechanical Ventilation Systems.įor an overview of whole-building ventilation systems and airflow requirement guidelines, see the description tab of the Building America Solution Center guides Whole-House Ventilation Strategies for New Homes and Whole House Ventilation Strategies for Existing Homes guides.

Determine whether alternative airflow methods and tools not covered in test standard ANSI/RESNET/ICC 380-2019 are suitable.Select an airflow measurement device with acceptable accuracy for the application.

Select a recommended location to make flow measurement that will result in acceptable accuracy.

Measure mechanical system airflow rates using reliable accurate equipment and methods.

Manual j cfm airflow test