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Aura Gravity Ventilator with Curb Mount Flange | 42″ Diameter 12″ Tall Collar AV-42-C12-CMF


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Brand: Active VentilationUPC(GTIN): 843951011448 SKU: AV-42-C12-CMF Category:

Aura Roof Vent - Curb Mount Flange Installation Instructions

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Aura Vent with Curb Mount - Technical Drawing Downloads

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Basic dimensions of the Aura Vent and it’s identifying attributes. Primary identifying dimensions of vents and fans are the inside diameter of the Head, which equals the diameter of the hole being vented, and the height of the Collar which is the solid tube between the Head of the vent and the Flange which attaches to the roof.

Inside Diameter:

42 in.
106.7 cm.

Outside Diameter:

48 in.
121.9 cm.

Square Flange (side length):

46 in.
116.8 cm.

Height of Head:

18 in.
45.7 cm.

Collar Height:

12 in.
30.5 cm.

Height of Flange:

3 in.
7.62 cm.

Total Height with Collar and Flange:

33 in.
83.8 cm.

Louvers are the vertical openings in the vent, which facilitates the flow of air, while keeping animals, insects, debris, and embers out.  The combination of inner and outer Louvers on our signature “Aura” series of vents and fans are shaped to create a positive vacuum effect which draws air out of the vent, utilizing a physical principle known as the Venturi effect.

Louver Height (inside):

14.5 in.
36.8 cm.

Louver Height (outside):

14.5 in.
36.8 cm.

Size of opening btwn blades (inside):

0.5 in.
1.27 cm.

Size of opening btwn blades (outside):

0.5 in.
1.27 cm.

Expected snow and rain in your region and the pitch of the roof are the key consideration when choosing the height of the collar of your roof vents. Zones 1 and 2 are not expected to sustain significant snow packs, while zones 3-7 are likely to experience snow, possibly for weeks or months. Vent collars under 4 inches are inappropriate for flat (0/12 pitch) roofs because even heavy rain can splash water into a shorter vent.

Map of Climate Zones

Minimum Pitch Capacity:

0/12 - 0°

Maximum Pitch Capacity (Standard Vent):

3/12 - 14°

Maximum Pitch Capacity (Modified):

12/12 - 45°

Free Air Space:

1385.4 sq. in.
8938.3 sq. cm.

Free Air Space:

9.6211 sq. ft.
0.8938 sq. m.

1:150 Ventilation Rule:

2886.34 sq. ft.
268.15 sq. m.

1:300 Ventilation Rule:

5772.68 sq. ft.
536.299 sq. m.

The Venturi effect stimulated by even small breezes creates a positive movement of air out of the vent without the need of any part of the vent to move. This movement of air is proportional to the wind speed, and can be measured in Cubic Feet per Minute or Cubic Meters per Minute.

4 MPH Wind:

1883 CFM
Airflow in 6.4 KPH Wind: 53.32 CMM

5.2 MPH Wind:

1931 CFM
Airflow in 8.4 KPH Wind: 54.68 CMM

7.4 MPH Wind:

2960 CFM
Airflow in 11.9 KPH Wind: 83.82 CMM

9.8 MPH Wind:

3331 CFM
Airflow in 15.8 KPH Wind8: 94.32 CMM

11 MPH Wind:

4997 CFM
Airflow in 17.7 KPH Wind8: 141.5 CMM

This is a premium exhaust roof vent, with a flange for easy mounting onto a roof curb, ideal for flat industrial roofs. Activated by even a small breeze to forcefully evacuate air using the Venturi effect, all Aura Vents use louver technology to keep your property safe, comfortable, and energy efficient.

Actual Package Weight 58 lbs
Dimensions 50 × 50 × 34 in
UPS Dimensional (Billable) Weight 612 lbs

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