Do Whirly Birds Work. This is when you need roof ventilation the most. It radically improves on the old whirly bird exhaust fan that relies on outside wind to drive the unit.
The top part of the whirlybird sports an arrangement of fins that can be easily turned by rising warm air and wind from outside. Whirly birds just by themselves are not very effective. The Solar Whiz is a remarkably clever and simple device.
This is when you need roof ventilation the most.
These installed vents may not be very air tight when they are closed up. But you need to calculate your roof space volume then work out how much airflow is needed and buy suitable fans. These installed vents may not be very air tight when they are closed up. Whirlybirds are popular because theyre cheap easy to install and require little to no maintenance once installed.