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How Effective Are Whirlybirds At Cooling A Roof? Simply put, whirlybirds are not effective at cooling a roof. Many people who buy whirlybirds do so because they are a well-known and seemingly cheap ventilation option. Most whirly birds have an airflow capacity of 100 cbm of air per hour when there is no resistance. This is not usually enough air movement to effectively remove hot air from your roof space. At Solar Whiz we find that generally, a minimum capacity of 700 cbm of air per hour is necessary to have a noticeable effect. Buying a whirlybird may seem like a straightforward decision because they are relatively cheap and a whirlybird installation doesn’t cost much. However, we would strongly encourage you to consider other options, as they aren’t very effective at keeping you cool.

Why Don’t Whirlybirds Work?

Whirly birds principally depend on wind to work. When there is a breeze, the turbines will spin, creating a vacuum that extracts air from the inside. That means that on a hot, still, summer day whirlybirds won’t do very much to keep you cool. Additionally, on windy winter’s day, the whirly bird will be extracting warmer air that you probably want to be keeping inside.
As we outlined in a previous blog post, a whirlybird is also prone to malfunctioning because of the exposed moving parts. That means you will need to periodically clean them out or lubricate them to ensure they keep working quietly.

How Can I Increase The Efficiency And Life-Span Of My AC?

Air conditioning with ventilation
Proper ventilation can be massively helpful for increasing the efficiency of air conditioners. Air conditioning units and ducting are most often kept in a house’s roof space. These spaces can reach up to 70° Celsius on a hot summer day. This puts a lot of pressure on the unit to keep itself cool as well as to keep your house cool.
With proper roof space ventilation, you can reduce the roof temperature close to the outside ambient temperature. That means that the air conditioning unit and ducting will stay much cooler and as a result doesn’t have to work as hard to produce cool air. This can increase the efficiency of your air conditioner by up to 20%!

The Solar Whiz Roof Ventilation Fan

Solar Whiz is a powerful solar-powered fan for ventilation. They are far more effective than whirlybirds at cooling a roof, with airflow capacities ranging from 1200m³/h to 2300m³/h in our domestic range. Our commercial fans can extract between 7,000m³/h to 10,000m³/h! The amount of air that whirlybirds extract in ideal conditions is still far less than you need for effective ventilation. At Solar Whiz, most of our customers need one or two of our mid-range or larger solar roof fans, the equivalent of 18-23 whirlybirds!
Solar powered fans are the best thing to cool down a room during summer because they are free to run and highly efficient. They are also well-regarded for their ability to increase the efficiency and lifespan of air conditioning systems. We find that most of our customers use their air conditioners far less after installing Solar Whiz because the solar roof fan is so good at removing excess heat from the house!

Frequently Asked Questions

What is the purpose of a whirlybird?

The whirlybird, also known as the turbine vent, is a semi-mechanical ventilation device that uses the wind to cool our homes. They resemble unique bulbs and feature fins on the outside of the body that allows the unit to spin in the wind.

What are the problems with whirlybird?

Whirlybirds need to be lubricated and cleaned in order to work properly, despite the fact that they are frequently thought of as something that can be installed and forgotten about.They’re not the most durable option because they are susceptible to rust and can be harmed by harsh weather.

What is an alternative to whirlybirds?

The Solar Whiz is a top-performing whirlybird alternative for roof ventilation. With its solar power, it effectively extracts heat, reducing build-up in the roof. It’s a powerful and easy-to-install solution that can replace many whirlybirds, making it an excellent choice for both businesses and homeowners.

How much ventilation does a whirlybird provide?

A whirlybird’s ability to move air depends on both the whirlybird itself and the area where it is mounted. Around 10 cubic metres of air per minute will be removed from the roof cavity by a whirlybird ventilator with a diameter of 30 cm and a wind speed of 8 km/h.

Why do whirlybirds stop spinning?

The corrosion or seizing of the bearings is the most frequent reason for whirlybird failure. This may cause the whirlybird turbine to make noise, slow down, or stop spinning altogether.