Australia's eastern coast has been relentlessly battered with heavy rainfall, strong winds, and dangerous flooding.

But aside from the obvious risks, heavy rainfall can also cause mould formation in the home, which can be harmful to your health.


Mould is a type of fungus that typically grows in dark, damp, and humid environments.

Dr Michael Taylor, a microbiologist and mould fungi expert, said that there were “several factors at play” that cause mould growth in homes affected by storms and flooding.

He said: “The increased rain has pushed up the relative humidity which means we’re seeing a lot more condensation, and moisture trapped in rooms and houses that can’t be ventilated or don’t have adequate ventilation.”

“Flooding has also impacted a lot of structures, which has led to trapped moisture in both absorbent items, as well as inside walls and other building structures, which is hard to remove and if it’s not dried within a few days can begin to support mould growth.”


Public health and occupational health scientist Brad Prezant pointed out that closed-off spaces — such as wardrobes and bathrooms — are the most conducive areas for mould growth, making them risky.

Mr Prezant explained: “That’s because there’s no ventilation in those areas.”

“If you don’t allow the air to circulate around stuff then you have a much higher likelihood that it’s going to be sucked into the material.”

How to mitigate mould growth

Now that we learned about the factors that can promote mould growth, we can take some measures to mitigate it.

Some steps that could be taken to prevent mould growth include having good ventilation inside your home.

It is also advised to watch out for "moisture-creating" activities — such as cooking without a range hood, drying clothes with a clothes dryer, and hanging wet clothes inside your home.

Mr Prezant said: “There are all these things we do indoors that create more humidity, so to the extent that you can manage these things you could have a big impact on the total humidity in the house.”

For those of you who use air conditioning units, it is advised to check if they come with a dehumidifier setting as dehumidifiers can help lessen the likelihood of mould growth.


For more detailed steps on how to lessen the likelihood of mould growth in your homes, we recommend this video:



Dangers of mould exposure

The most commonly known risk of close contact with mould is the fact that it releases spores into the air that can cause respiratory problems, especially in people who are already susceptible to them.


While this holds a certain level of truth, Dr Taylor said that we should remember that we inhale "100s to 1000s" of different mould spores every day.

He said that although he would "always recommend" staying in a house with mould, it should be noted that the level of risk posed by mould varies significantly from person to person.

“It really depends on how much mould is there, and it’s worth mentioning that we’re exposed to mould spores all the time, and thankfully most people don’t tend to react strongly to it,” Dr Taylor said.

“There are several groups of people who are at higher risk, particularly those who are immuno-compromised who can develop serious illness and should do as much as possible to avoid living or sleeping in mouldy bedrooms.

“There is a subset of people who are sensitive to mould spores, particularly those with asthma who may show symptoms such as itchy eyes or skin, shortness of breath or allergy type symptoms.”


Additionally, both Dr Taylor and Mr Prezant claim that a small amount of mould is relatively harmless, with Mr Prezant saying: “You should be concerned if you have significant amounts of mould and your concern should track with the quantity in surface area.”

Dr Taylor also said that mould growth that is “smaller than an A4 page" poses low risk of health complications.

"But once you start reaching larger impacted walls and bigger mouldy items you should try to limit your exposure as much as possible, particularly if you know you’re within any of those risk groups,” he warned.

Additionally, Dr Taylor pointed out that some household items need to be discarded when mould starts growing on them.

The items that you should keep an eye out for include "couches that are fully soaked with floodwater" and other items made from porous materials.

Meanwhile, non-porous items, such as those that are made of hard plastic, only need to be cleaned before reuse.

We hope this article helps you to prevent mould from growing in your homes. Keep safe, folks!

For those who are struggling to remove the mould buildup from their homes, we recommend checking out this video: