Whirly birds or turbine ventilators have been around since Adam was a boy. The fact that whirly birds spin around with the wind makes people believe they actually do something to remove hot and moist air from the roof space - well this is simply not true.
The fact is the only hot air involved is the hot air that comes from the sales people who market these monstrosities. I guess they have price in their favor but what’s the point of paying any sort of money for a product that does not do anything other than spin around. It’s no different than the placebo pill and your house is going to look like a factory – check out Case Studies and Reports on this site – “Whirly Birds Don’t Work” – you will see a report from Deakin University’s technical testing unit MABEL, with infrared state of the art equipment proving this fact.
The other factor is why waste your money on a product that hasn’t changed with technology for over 100 years except for the fact that plastic fins and rotors etc may have been placed inside the turbine further restricting any airflow.
If you are serious about roof ventilation, if you want cooling for the home in summer and release of unwanted damaging heated air locked in the roofspace in winter, you can’t go past Universal Tile Ventilators.
Prepared to be amazed.