Ventilation Calculator

Click the download link below to save the Attic Ventilation Calculator to your computer. This simple Excel file will quickly and easily calculate your attic ventilation needs.

To use this tool, first unzip the file to your desktop. Then double-click the file to launch it in Microsoft Excel. At the top of the page, enter the square footage of your attic and press the Enter key. The amount of intake and exhaust ventilation for any size attic is immediately calculated for each ventilation product type!


New! Download the Ventilation Calculator directly to your smartphone or tablet.



1) Check the installation instructions for roof pitch requirements for all products.
2) Calculations (except Power Vents) are based on the Code Minimum 1 square foot of Net Free Area for every 150 square feet of attic floor space balanced between Exhaust and Intake Vents. To achieve the allowable Code Exception of 1/300, use half the number of vents specified.
3) Power Vent calculations are based on attic square footage multiplied by 0.7.



Customizable Ventilation Calculator


Our Ventilation Calculator allows you to add your company logo, colors, and a personalized message. Use our exclusive tools to make it your own and present your customer with a company-branded summary of their attic's ventilation needs.

Ventilation Calculator

To start customizing, click the DOWNLOAD button in the calculator at the top of this page.


Ventilation Calculator


If you're having any difficulty viewing the calculator above, try downloading the file directly by clicking this link.




Air Vent Contractor LocatorOur exclusive Contractor Locator will allow you to find contractors in your area who can assist with Air Vent product installation—including solar attic fans and skylight tubes. Click the link below to register and get started.


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