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Whole house fans, exhaust and ventilation fans and Indoor Air Quality
Tamarack Technologies Fans - Fan Size Calculator

 

Fan Requirement 

To calculate the fan capacity for any home, use this formula to determine the CFM (Cubic Feet Per Minute)

Exhaust Requirement

After selecting the proper fan size, verify that you have an adequate amount of Net Free Vent Area (NFVA) in your attic to allow the fan to work at peak efficiency. 

Make sure you have one square foot of NFVA per 750 CFM fan capacity per Title 24 guidelines. 

 

Finally, after determining the minimum NFVA needed, the existing vents in your attic will need to be measured to verify you have enough venting. 

Windows must be opened to safely and effectively operate a whole house fan.