"My clients and I have worked with Jan Frutiger and A-Ball for over 20 years. Jan knows more about plumbing fixtures and fittings, from budget to historical correctness, than anyone I've ever worked with."
Lawrence Nelson, Architect Portland, Oregon
Panasonic® Fan Sizing Chart
The Home Ventilating Institute (HVI) recommends the following Air Changes per Hour (ACH):
Static pressure in a typical duct run is caused by the type of duct material, elbows, exterior or wall cap, etc. The table below shows the standard values for duct components.
The chart allows you to calculate the equivalent straight duct length in order to overcome static pressure caused by each component in a duct run.