People with weakened immune systems or chronic lung disease are the group Australian health guidance singles out as most at risk from indoor mould, including the risk of mould infection in the lungs. If a person in that situation lives in a home with mould, the tolerance for leaving it until later should be lower: they should stay out of affected rooms, never clean mould themselves, and be away from the home during remediation. Their GP or specialist is the right person for any health question.
This page is for families, carers and property managers arranging the building side.
Who is at higher risk
NSW Health’s mould factsheet says people with weakened immune systems (it gives the examples of people with HIV infection, cancer patients having chemotherapy and organ transplant recipients) and people with chronic lung diseases such as COPD and emphysema are more at risk of mould infection, particularly in the lungs. People with asthma, allergies or other breathing conditions may be more sensitive to mould generally.
The Western Australian Department of Health’s 2024 review, Indoor Mould: Health Risk Assessment and Management, adds that healthy people exposed to indoor mould do not usually develop invasive fungal infection, but that such infections in immunocompromised people are a significant and emerging challenge, and that it is widely accepted by Australian health departments that immunocompromised people should be protected from mould exposure.
Age on its own is not one of the groups NSW Health names. What matters is the person’s health: immune-suppressing treatment, lung disease, asthma or allergies. If you are unsure where an older parent fits, ask their GP.
Signs the home needs attention
- A musty smell in the bedroom, living room or wardrobes, which people who live with it every day often stop noticing; visitors notice it first
- Visible mould on ceilings, window reveals, behind furniture or in wardrobes
- Window condensation that lingers most of the day
- Relative humidity regularly above the US EPA’s recommended ceiling of 60 percent, measurable with a cheap hygrometer
- Respiratory symptoms that ease when the person is away from home and return when they come back (raise this with their GP)
What carers and families can do now
| Action | Why | Who |
|---|---|---|
| Fix leaks and damp sources | Removes what feeds the mould | Plumber, roofer, builder or property manager |
| Check exhaust fans vent outside | Gets steam out of the house, not into the roof | Electrician if the fan needs re-ducting |
| Run a dehumidifier in damp rooms | Lowers humidity without relying on open windows | Carer or family; see dehumidifiers and mould |
| Keep the person out of affected rooms | Reduces exposure while the cause is fixed | Family and carer |
| HEPA air purifier in the bedroom | Captures airborne spores in that room | See air purifiers for mould |
| Remove visibly mouldy soft furnishings | Takes a spore source out of the room | Carer or family, with gloves |
Do not let the vulnerable person clean mould, and don’t have a carer scrub large areas without protection. The WA review lists immunocompromised people and people with respiratory conditions among those who should avoid doing remediation themselves.
When it needs a professional
The WA review classes mould as “complex”, typically needing professional help, when growth is larger than 1 square metre or in multiple rooms, keeps recurring, is in a ducted heating or cooling system, or comes from a building fault that is hard to repair. With a vulnerable occupant, it is reasonable to get professional advice earlier than that.
A mould inspection and moisture investigation finds the moisture source with moisture meters and thermal imaging and produces a written report. That report is also something the person’s GP or specialist can read if they are seeing recurring respiratory problems.
Planning remediation around a vulnerable person
When mould remediation goes ahead, these points matter more than usual:
- Relocate before work starts. The person should be out of the home for the whole job, not just the day the mould is cut out. Choose a dry, well-ventilated place to stay, not another damp house.
- Tell their treating team. Let the GP or specialist know that remediation is happening and when the person will return; they may have specific advice.
- Ask about containment. Ask the contractor how they will isolate the work area (sheeting, sealed doorways, HEPA-filtered air) so dust and spores don’t spread through the house.
- Agree the finish line before work starts. Ask how completion will be confirmed: a visual check, moisture readings, and where justified, sampling. The post-remediation verification guide explains what that involves.
- Get a written re-occupancy point. A specific condition or time from the contractor, confirmed with the person’s doctor if they are on immune-suppressing treatment.
- Tell home care providers about the temporary address and dates.
- Fix the cause. Remediation without fixing the moisture just resets the clock.
Rentals and aged care
In a rental, NSW Fair Trading’s guidance on mould says the landlord is responsible where mould comes from a building problem such as a defect not repaired in reasonable time or inadequate ventilation, and that tenants must report mould or damp as soon as possible. Put the request in writing, mention the occupant’s health, and attach photos. This is general information, not legal advice.
In a residential aged care facility, raise it with management first. If it isn’t resolved, the Aged Care Quality and Safety Commission takes complaints about aged care services.
Next step
Describe what you’ve found, the occupant’s situation and the suburb on the contact form. The enquiry goes to an independent local professional, who can talk through inspection, timing and access around the person’s needs.
Frequently asked questions
Who is most at risk from mould in the home?
NSW Health names people with weakened immune systems, such as those having chemotherapy or with an organ transplant, and people with chronic lung disease such as COPD, as more at risk of mould infection. People with asthma or allergies may be more sensitive.
Should an elderly parent with breathing problems get their home checked for mould?
If the home has a musty smell, visible mould or constant condensation, yes. An inspection either finds something fixable or rules the home out, and the decision should involve their GP.
Can carers clean small mould patches?
A carer, not the vulnerable person, can clean a small surface patch with gloves, eye protection, good ventilation and a mild detergent or diluted vinegar solution, as NSW Health suggests. Anything larger or recurring needs a professional.
Should the occupant leave home during mould remediation?
Yes. Someone with weakened immunity or lung disease should be away for the whole job and return only at a written re-occupancy point agreed with the contractor and, where relevant, their doctor.
Who do I contact about mould in an aged care facility?
Raise it with the facility’s management first. If it isn’t resolved, the Aged Care Quality and Safety Commission handles complaints about aged care services.