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ASHRAE 62.2-2010 Tool Guide

What this tool does – [Tool]

The ASHRAE 62.2-2010 RED Calc tool handles all the requirements of the Standard, including new and existing buildings, the alternative compliance path, and infiltration credit. We have added useful features, including the advanced blower door inputs option and the fan-run time option for intermittent operation of whole-building ventilation.

Calculated values

  • Natural airflow.
  • Whole-building required airflow.
  • Alternative compliance supplement.
  • Infiltration credit.
  • Whole-building mechanical ventilation.
  • Fan run-time per hour.


  • Clicking the label for any input or result will cause a popup help box to appear. This help box includes the allowed and normal values (for inputs).
  • Tool handles existing and new construction.
  • Weather data is included for the United States and Canada.
  • You may choose to use the Advanced Blower Door Inputs to adjust your results for temperature, altitude, or pressure exponent.
  • You may choose to use the Local Ventilation Alternative Compliance feature for existing dwellings. This feature includes one kitchen and from one to five bathrooms.
  • The Whole-Building Ventilation Run Time tool allows you to determine run-time per hour if you wish to operate the whole-building fan intermittently.
  • You may use this tool to comply with the ASHRAE 62.2-2007 Standard: For new dwellings, simply select New for the choice “New or existing construction”. For existing dwellings, select Existing for the choice “New or existing construction”, select Yes or No for “Use infiltration credit”, and make sure “Use Local Ventilation Alternative Compliance” is not checked.
  • The ASHRAE 62.2 Standard is written as a minimum standard; you may exceed the minimum requirements of the Standard.


Although the first version of the ASHRAE Standard 62.2, Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings, was published in 2003; the 2010 version was the first to gain national attention.

The Wisconsin low-income weatherization program was the first organization to adopt the residential ventilation/IAQ standard, in late 2004. As of the end of 2012, they had installed ASHRAE 62.2 ventilation in over 20,000 homes.

The adoption of the ventilation/IAQ standard gained momentum in 2011 when the Department of Energy required the use of ASHRAE 62.2-2010 in the low-income weatherization program by the end of the 2012 program year. In 2013 the Building Performance Institute (BPI) adopted the 2013 version of the standard.

The adoption of ASHRAE 62.2 makes obsolete the use of the Building Tightness Limit (BTL or BTLa), the Building Airflow Standard (BAS), and the Minimum Ventilation Rate (MVR). These methods were based on the obsolete ASHRAE 62-1989 standard.

Best Practices

The ASHRAE 62.2-2010 Standard allows the use of the alternative compliance path (Appendix A of the Standard) for existing dwellings. This path allows compensation for deficits in local ventilation (kitchens and bathrooms) by increasing the flow rate of whole-building ventilation. Generally, the use of this alternative path saves money and installation time, but it might result in lower indoor air quality. Whenever possible, do not use the alternative compliance path.