Osbournes Grilles, Diffusers & Louvres


WPL50 Louvre Selection

A weather resistant louvre ideal for commercial and residential ventilation applications. Also used in commercial window and door joinery. The WPL50 Louvre comes in a channel or a flange frame option, with birdmesh fitted to rear as standard.

WPL50 Perfromance
Tested at Auckland Ventilation Services, Sept 2000.
Test results available on request.

Performance Chart

Example: To select a louvre to exhaust 0.595m3/s with a pressure drop of 20Pa.

Step One:

From the Performance Chart, select the Pressure Drop of 20 Pa. Plot across to the exhaust curve. Then plot down to the indicated free Area Velocity e.g. 4.3 m/s.

Step Two:

Calculate the required Free Area of the louvre.
Free Area = Volume Flow Rate/Free Area Velocity
Free Area = 0.595 (m3/s)/4.3 (m/s) = 0.13 (m2)

Step Three:

Select a suitable louvre from the Free Area (m2) table. Some suitable louvres from the Free Area Table are:

0.500m wide x 0.800m high
0.600m wide x 0.700m high
0.300m wide x 1.400m high
0.450m wide x 0.900m high