Most people do not know how whirlybirds in Australia work. They do not appreciate that whirly birds are only part of a venting system for roof attics.
Attic ventilation means air replacement. And this means that air exhausted has to be replaced by fresh air intake. Therefore whirly birds have to be paired with inlet vents for the system to work.
Most whirly bird installations in Australia lack the inlet vents. Therefore, they do not work.
The new Australia National Construction Codes require all new roof in major Australian cities to have roof attic ventilation. This new building requirement will birth a demand for roof attic ventilation systems.
So, will the old whirly birds now become the first choice for ventilation compliance?
And what are the challenges of using whirly birds to ventilate the roof attic?
All this will be discussed on this video.
https://www.roofingportal.com.au/