skip to Main Content

Aura Retrofit Gravity Vent | 48″ Diameter AV-48-RF


  • All our aluminum products can be painted with a durable baked-on powder coating surface finish.

    • 0 $
    • 200 $
    • 400 $

    Hover (or tap once) to show color with name, Click (or tap again) to select.

    Hover (or tap once) to show color with name, Click (or tap again) to select.

Brand: Active VentilationUPC(GTIN): 843951001326 SKU: AV-48-RF Category:

Shipping Dimensions for AV-48-RF


Active Ventilation Products

Click here for -> Shipping / Delivery - Policies and Procedures

Click to enlarge pdf for print
Retrofit Aura Vent Cap AV-48-RF-cut-away-and-measurements

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:

54 in.
121.9 cm.

Outside Diameter:

54 in.
137.2 cm.

Retrofit Stop Rib:

5.1 cm.

Height of Head:

18 in.
45.7 cm.

Diameter of Retrofit Opening:

Total Height of Retrofit Vent:

20 in.
50.8 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.
1.3 cm.

Size of opening btwn blades (outside):

0.5 in.
1.3 cm.

Free Air Space:

1809.6 sq. in.
11674.5 sq. cm.

Free Air Space:

12.57 sq. ft.
1.167 sq. m.

1:150 Ventilation Rule:

3769.91 sq. ft.
350.236 sq. m.

1:300 Ventilation Rule:

7539.82 sq. ft.
700.472 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:

2825 CFM
Airflow in 6.4 KPH Wind: 80 CMM

5.2 MPH Wind:

2896 CFM
Airflow in 8.4 KPH Wind: 82.01 CMM

7.4 MPH Wind:

4440 CFM
Airflow in 11.9 KPH Wind: 125.73 CMM

9.8 MPH Wind:

4997 CFM
Airflow in 15.8 KPH Wind8: 141.5 CMM

11 MPH Wind:

5711 CFM
Airflow in 17.7 KPH Wind8: 161.72 CMM
Click to enlarge pdf for print


4 inch diameter vent with an adapter fit over an existing 4 inch diameter turbine base or vent pipe Aura Ventilator Retrofit kits will easily fit over old bases and old turbine bases. Easy quick installation. Balancing is not required, just slip the new vent over an existing base. The Aura Vent Retrofit will never rust, no maintenance required and snow or rain will not infiltrate inside the Aura Vent. It is quite and will never wear out due to no moving parts!