Proper attic ventilation consists of a balance between air intake and air exhaust.

The U.S. Federal Housing Authority recommends a minimum of at least 1 sq. ft. of attic ventilation (split between intake and exhaust) for every 300 sq. ft. of attic floor space.

Use this calculator to help determine the proper amount of air exhaust panel vent attic ventilation based on U.S. FHA 1/300 guidelines.

To calculate the total square feet, measure the length and width of the attic floor space to be ventilated.