Although not an overly pleasant issue for landlords or tenants to deal with, mould is a serious issue for any household that can be difficult to properly remove, and even have serious health implications.

What is it and how does it spread?

According to NSW Government Health, mould is in the same group of common fungi that includes mushrooms and yeast and will commonly grow on organic materials such as timber. Damp or moist environments with little to no ventilation are perfect conditions for mould to grow; bathrooms are obviously common places for mould to appear, but any areas with similar conditions could see mould growth.

Unfortunately, drying out damp areas in which mould is present only makes getting rid of it that much more difficult. Mould spreads by releasing spores to new areas. If it is dried, the release of spores increases to keep the mould alive. Drying the area and removing any moisture can sometimes not work as the mould only spreads more.

Common causes for mould

Lack of ventilation can be a common cause for mould to grow. Bathrooms are a common place for mould to appear due to the moisture and humidity from showers or baths, but only if there is poor ventilation. For example, a faulty exhaust fan is one of the quickest ways to create conditions perfect for mould. Opening a window (where possible considering privacy) will help ventilate the room, but prevention is easier when a fully operational exhaust fan is available.

The bathroom is not the only place where mould can grow. Not opening windows and allowing fresh air to flow through the property will contribute to the likelihood of mould growing, especially if moisture is present. Water leaks, moisture in the sub-floor areas or structure of the building, even leaving wet clothes in a pile can contribute.

Mould is a serious health issue

Aside from being hugely unpleasant to look at, mould is a serious health issue. Most people would have lived in properties that have been less than clean (university share houses), dotted with patches of mould in the kitchen or bathrooms. Most people would only regard it as a fairly gross thing to look at and clean it once they absolutely had too.

However, mould is more than an eye sore. It can also be a serious health issue. Mould can cause significant respiratory problems including sneezing, coughing, or even wheezing. These problems can be further compounded for people with respiratory conditions such as asthma. The young and elderly are also more susceptible to health issues as a result. Mould needs to be taken seriously as a health consideration and not just an unsightly inconvenience.

Removing Mould

The best cure for mould is prevention. Keep all rooms well ventilated and ensure any moisture is dried quickly. However, if mould is present, in all likelihood more will need to be done than just spray it with bleach or a mould remover.

Removing mould can be an involved process. Firstly, ensure you are able to clean the mould yourself. According to Victorian Government Health, people with weaker immune systems, respiratory issues, or lung diseases would be advised to not clean mould themselves and instead engage a professional.

If you are cleaning it yourself, there are a few basic steps to undertake to remove the mould.

Firstly, ensure there is no residual moisture present. The mould will just return if there is still moisture.

Most household detergents can be applied to mould, although be sure to read the label to make sure the product is suitable to clean mould. Failing that, a more home grown approach of a vinegar and water solution can be applied, according to NSW Government health.

The area can then be dried thoroughly once the mould has been cleaned away, making sure that any moisture has been removed and will not come back.


The responsibility to remove mould will depend on the circumstances in which is occurred. If a faulty exhaust fan leads to mould in a bathroom, it is likely that comes under maintenance and therefore it would be the responsibility of the owner to rectify.

If there were no maintenance issues such as faulty fans or water leaks and the mould was caused by the tenant simply not opening windows or using air conditioners to ventilate the property, then it is likely an issue for the tenants to resolve.

Each state is different depending on who will be responsible for the removal of mould depending on each situation. Tenants and landlords should speak to their property manager and research the issue as the work to a resolution. For example, the Residential Tenancy Authority in Queensland lists situations in which either tenants or landlords could be responsible:

  • “It is the responsibility of the tenant to notify the property manager/owner of any serious/extensive mould problem.
  • If the mould is a result of an issue in the property, such as a roof leak, it is generally the property owner/landlord’s responsibility to clean the mould and make any repairs necessary to maintain the property in good repair.
  • If the tenant caused the mould, they are responsible for its removal and may have to pay for to repair any damage caused.
  • At the first sign of any problem, the property manager/owner and tenant should discuss the issue.
  • An example of who’s responsible: if the tenant continually allowed steam to build up in the bathroom without proper ventilation and/or regular cleaning, resulting in mould, then the tenant may be liable. If the mould is a result of a structural issue, e.g. a roof leak, then the lessor would be liable for the repairs.”

More information

For more information on dealing with mould, speak to a mould professional or check out these links: