Venting Requirements Calculator
for AVP Universal Vents

Based on the 1/300 Rule
(see Building Codes menu for more info)

To determine how many Universal Vents are required
to properly ventilate an attic space:

Enter the length of
the building in feet
Enter the width of
the building in feet

Choose the desired vent




vents required - 1/300 rule



vents required - 1/150 rule

Enter the total area of attic
in square feet


Choose the desired vent




vents required - 1/300 rule



vents required - 1/150 rule

OR

Application: One vent for exhaust per:

Vent
Diameter
Sq. Feet
of Floor
1/150
Sq. Feet
of Floor
1/300
Net Free
Vent Area
in Sq. Inches
Net Free
Vent Area
in Sq. Feet
UV-15
31.3
62.5
15
0.104
UV-30
62.5
125.0
30
0.208
UV-45
93.8
187.5
45
0.313
UV-60
125.0
250.0
60
0.417
UV-75
156.3
312.5
75
0.521
UV-90
187.5
375.0
90
0.625
UV-105
321.0
437.5
105
0.729
UV-120
366.0
500.0
120
0.833
UV-135
412.0
562.5
135
0.938