When building occupants discover indoor mould, there is typically a sense that something might be wrong.

Too often, however, such concerns are met with indifference from building practitioners who brush it off under an approach of ‘she’ll be right’.

In fact, I rarely come across designers, builders or building surveyors who can articulate the risk from mould or appreciate the degree to which its presence is a cause for concern.

Once, I was asked if mould was the next asbestos.

I wish I had an easy answer.

On one hand, asbestos can affect any person who is exposed to it. By contrast, the effect of mould varies according to the degree to which individual occupants are susceptible to it.

Nevertheless, a particular characteristic of mould is that it cannot be left alone and will deteriorate if action is not taken to address underlying moisture problems. Asbestos, by contrast, can be left undisturbed so long as it is non-friable and in good condition.

This article describes the effect of mould on health. It will examine the prevalence of mould-related defects, how mould affects our health and what we need to know about the emerging field of study into biotoxin illness.


Recent Victorian Mould Cases

I have collected mold-related news for the past seven years.

Whilst there have always been accounts of mouldy buildings, the number of reports has grown over recent years. This is particularly the case in Melbourne, which has had the longest COVID lockdown.

Consider the following:

  • A lawyer from Tenants Union Victoria indicated that every winter, the organisation was inundated with calls and emails – one quarter of which were seeking advice about mould (Asher, 2020). COVID restrictions have meant that during lockdown, most tenancies could not be inspected before moving in. Some of those who felt their dwellings were making them sick were either forced to stay in apartments (Williams, 2021) or, for a Kensington resident, to leave the apartment for respite at a park in breach of public health orders (Asher, 2020).
  • A purchaser of a $480,000 home in Pakenham who was immunocompromised and had recently undergone chemotherapy was forced to fork out $25,000 for remediation after the seller took no responsibility for failing to disclose the extent of mould in the house (Vincent, 2021). Although these purchasers had not engaged a pre-purchase inspection, it is doubtful that this would have made any difference since the standard for Pre-purchase Inspection of Residential Buildings (AS 4349.1, Standards Australia, 2007) does not include reporting on mould as part of its inspection scope.
  • A Melbourne resident was not able to find visible mould despite environmental testing revealing elevated mould levels. She said, “We didn’t realize it was mould because we couldn’t see anything. So it must have been painted over or something” (Salmin, 2021).
  • A Hawthorn apartment, which sold for $672,000, was experiencing balcony leakage causing soggy carpets in the bedroom each time it rained. The owner’s doctor subsequently took a nasal swab and discovered it blackened with mould spores (Williams, 2021).
  • In a newly built apartment in Caulfield, costing almost $1.3 million, differing opinions were presented on the cause of mould on the ceilings, curtains and carpets in every room. Inspectors sent by the developer and builder attributed it to condensation caused by a lack of ventilation. However, an independent inspector found the water ingress to originate from a failed waterproofing of the overhead slab (Cook, 2021).


Water damage in apartments

In building audit reports covering NSW, QLD and VIC, 85 percent of buildings had at least one defect across multiple locations (Johnston & Reid, 2019). Water ingress and water-related problems were found to be the most prevalent contributor to defects, accounting for 29 percent of defects.

In a recent survey conducted by the AAA (Australian Apartment Advocacy, 2021), 52 percent of the 1,044 respondents from Victoria had experienced defects. The table below displays the range of defects. As shown, the most commonly reported defect was again water-related, here presented as ‘water penetration from outside’. This was reported by 35 percent of respondents. Overall, 23 percent of those who have experienced defects have had all their defects fixed, while 23 percent had not had any of their defects fixed.


Dampness and health

In a 2009 review of literature, the World Health Organisation (WHO, 2009) concluded that there was sufficient evidence from studies which were conducted in different countries and undertaken in different climatic conditions to show that occupants of damp or mouldy buildings are at greater risk of respiratory symptoms, respiratory infections and exacerbation of asthma. This was true in both public and private buildings.

As shown in the following table, this finding is also reflected in health advice from Australian States and Territories.

Mould creates a variety of health problems.

In particular, it can:

• be allergenic and exacerbate asthma
• affect those who have compromised immune systems by invading and colonising the lungs, and
• create chronic inflammation in individuals with a genetic predisposition.

On that last point, inflammation is complex in that it involves multiple organs and can invoke multiple systems. When presented with mould patients, not all physicians are able to fully understand these complex inflammatory systems (McGowan, 2018).

In 2018, the Parliamentary Inquiry into Biotoxin Illness in Water-Damaged Buildings examined the prevalence of CIRS (or biotoxin-related illness), available treatment options and research into the causes from water-damaged buildings. Following this, the Commonwealth endorsed recommendations to raise awareness of CIRS amongst the medical community and to have building codes and standards regularly updated to reflect growing awareness of this built environmental illness (Commonwealth of Australia, 2018).
As a result, in July, the NHMRC (National Health and Medical Research Council) opened a special grant of $2m into biotoxin-related illnesses.
CIRS, or biotoxin illness

CIRS-WDB, (Chronic Inflammatory Response Syndrome in Water-Damaged Buildings) was first coined by Ritchie Shoemaker, a physician who found mould patients presenting similar symptoms to those who suffered from toxic algae bloom (dinoflagellate toxin exposure) he had treated elsewhere. For those who are genetically susceptible, biotoxins from mould accumulate and lead to an over-sensitised immune response. This places the patient under chronic inflammation.

According to Shoemaker, genetically susceptible patients suffer more from their overactive defence mechanism than from the invading biotoxin itself. He created a protocol around the diagnosis and treatment of the syndrome termed CIRS-WDB. According to his estimates, 24 percent of the population are genetically exposed to develop CIRS if they are exposed to a water damaged building. As a reference, by comparison, 11 percent of Australians have asthma.

This is particularly problematic given the number of buildings which are affected by mould. In North America it is estimated that up to 40 percent of buildings have mould (Sivasubramani et al., 2004). In Australia, 40 percent of all residential buildings are estimated to have condensation problems (ABCB (Australian Building Codes Board), 2016). Add in other problems of water ingress along with waterproofing and the incidence of mould becomes even higher. As such, it is highly likely that susceptible individuals will encounter problematic buildings on a daily basis.

For CIRS patients, the need to vacate from water damaged buildings is non-negotiable in order for treatment to work. In an experiment to test the efficacy of a biotoxin binder cholestyramine, 14 patients in a double-blind, placebo-controlled, clinical trial (Shoemaker & House, 2006), patients were (1) exposed to a water damaged building, (2) treated with cholestyramine, (3) ceased cholestyramine, (4) re-exposed to the building that caused the sick building syndrome and (5) treated with cholestyramine again.

So long as study participants avoided exposure to water damaged buildings, the researchers noted that the health of patients continued to improve following CSM (cholestyramine) therapy. When exposed to WDBs, however, all participants relapsed within seven days.

In another comprehensive literature review on the harmful effects of biocontaminants, Thrasher and Crawley (Thrasher & Crawley, 2009) reached a similar conclusion. They urged the medical profession to recognise the need to immediately remove occupants from the toxic environment. Thrasher also cautioned that it was virtually impossible to eradicate a systemic mould problem from a building. This arises from buildings with designed-in and/or built-in water-related problems.

It is extremely concerning that dwellings can not only be deemed uninhabitable but also irreparable. This is not an exaggeration. In some cases, restoration works have only temporarily removed mould without dealing with underlying problems. This was seen in America with Hurricane Sandy, “Since there is no current standard requiring that mould workers be trained and mould remediated to evidence-based standards, residents in mould-infested homes are left largely to fend for themselves—not just to remediate mould, but potentially to rebuild for a second time.” (ALIGN, 2013)


Toxic Mould Support Australia (by Richard Barry)

In the absence of recognition of CIRS from the general medical community, patients have suffered in silence and turned to support groups on social media. One such group on Facebook is Toxic Mould Support Australia (TMSA). Started in 2013, this is administered by volunteers who have suffered mould illness from exposure to water damaged buildings and now has 8,300 members (June 2021).

Common complaints among the TMSA community from exposure to water damaged buildings include autoimmune conditions, brain fog, sinus problems, allergies, fatigue, rage, neurological symptoms, gut issues, depression, anxiety, rashes and other skin breakouts.

In many cases, these symptoms reached levels that limited the ability of those affected to function and led to job losses, financial hardship and high medical costs.

Occupants also reported relief from symptoms upon leaving the water damaged buildings only for symptoms to return upon re-entry. As a cruel irony, a recurring sentiment was that ‘living in mould’ made one so sick that they were unable to leave and were forced to remain in the mouldy environment.

Among TMSA members, the consensus appears to be that any water damage or intrusion needs to be rectified within 48 hours in order to prevent a mould problem from occurring. Outside this window, members reported that mould progressed beyond surface level and was not able to be repaired without removal and replacement of building materials.

It was widely reported by TMSA group members that remediation rarely occurred within this window. Many group members expressed that landlords refused to fund the work required to properly address the mould problem and instead offered band-aid solutions such as concealment by paint.

Many of those whose tenancy cases ended in tribunal hearings spoke of difficulty in establishing the burden of proof without costly legal advice and expert documents. Of particular difficulty was demonstrating that the premises was not fit for occupation. Even when the tribunal was presented with copious substantiating documents, a number of claimants still lost. Those who succeeded often expressed mixed sentiments that in hindsight the compensation was not worth the trouble.

Overall, not many TMSA members were in a financial position or emotional headspace for a prolonged legal battle. Despite an intuitive sense that a mouldy residence was problematic, the lack of awareness of CIRS in mainstream medicine, together with a highly complicated construction litigation process, had resulted in these occupants opting to accept substandard living conditions instead of fighting what they felt to be an incomprehensible system.


US photographer, Thilde Jensen, travelled across her country to document people who had extreme chemical and electrical sensitivities. Her photobook, aptly named The Canaries (Jensen, 2013), documents the stories of people who have had to make extreme adaptations to continue living in their houses, or have had to live in cara, caravans or tents. Most people with CIRS also manifest a measure of either, or both, sensitivities.

Her work is a visual insight into a world we do not often encounter, of what a CIRS patient has endured when buildings fail them.

The profound impact of buildings on health is seen in the extreme measures in which the chemically sensitive have to take for ordinary activities of life. Clockwise from top-left: Randy in the car that was his home for many years. Tucson, Ariz., 2005. Caught in a net. Truxton, N.Y., 2010. Marie in her safe bedroom. Texas, 2011. Jen stuck in the tub too fatigued to move. New York, 2007.
Photos by Thilde Jensen, thildejensen.com
© Copyright, The Canaries, 2013. Used with permission.


I would reason that health and safety in buildings must be higher priorities compared to energy efficiency and accessibility. Thus I find it incoherent that whilst we are trying to make buildings more energy efficient and universally accessible, we have not been making a similar effort to ensure that buildings are universally healthy.

For the emerging group of people diagnosed with CIRS, the built environment has been and will be failing them. As homeowners are becoming more observant of mould occurring in their homes, building practitioners need to be acutely aware of the health ramifications of mould. The quality of a building cannot be distinguished from the quality of life that an occupant has in the building. It is no longer acceptable for building practitioners to be cavalier when mould appears in their buildings.