Whirlybird Removal and Patching

Whirlybirds are a popular and affordable, yet sometimes problematic, ventilation solution for Australian homes and buildings. Designed to expel hot, stagnant air from roof spaces, they provide a wind-powered method of improving airflow within a property, reducing the risk of mould and dry rot within buildings.

However, despite their initial cost-effectiveness, whirlybirds come with several drawbacks that can frustrate property owners. Their effectiveness depends on property size, with multiple whirlybirds often required to provide sufficient ventilation. A general rule of thumb is one whirlybird for every 50 sqm of roof void space. Notably, whirlybirds depend on wind - no wind, no ventilation. On calmer, less windy days, whirlybirds may fail to ventilate properly, making them redundant. Lastly, faulty installation or damage to a whirlybird’s seals and flashings can lead to water leaks and compromise ventilation effectiveness.

One of our recent jobs involved removing a whirlybird installed above a factory unit after the tenant reported a leak inside. Upon inspection, we found that the whirlybird was the likely source for the water leak. It had also become redundant due to the installation of a newer ventilation system and air conditioning units.

With the whirlybird no longer serving a useful purpose, we proceeded with its removal.

To rectify the leak and to ensure the roof became watertight once again, we patched the redundant whirlybird penetration and installed a galvanized tray extending from the ridge to 20 mm beyond the sealed area.

We installed the tray to provide an extra layer of weatherproofing, helping to divert water away from the patched section and prevent future leaks.

Removing unnecessary or outdated roof components can improve both the structural integrity and efficiency of a building. If you're experiencing leaks or have concerns about your roof ventilation, it may be time to assess whether your Whirlybird is still serving its intended purpose.