What causes mould?
Simply put, moisture causes mould.
"People have no idea how much a little water can do," says Dr Heike Neumeister-Kemp, chief mycologist (mould expert) from Mycolab.
A leaky roof, broken pipes, cracked roof tiles, windows left open while it's raining or a flood can cause moisture to enter your home. Or you could be
creating the moisture within the home itself: through air drying clothes indoors, running appliances without an exhaust, or by under- or over-heating your
home in the winter or over-cooling it in the summer.
It's important to figure out what's causing your mould problem and to fix the underlying issue, otherwise it will continue to occur, regardless of how
thoroughly you may think you've cleaned.
What's the problem with having mould?
Moulds can give off toxic chemicals, called mycotoxins, and if there's a lot of mould it can be dangerous – possibly resulting in hypersensitivity or allergic reactions, and asthma and flu-like symptoms.
Who's responsible – landlord or tenant?
So you've moved into a new place. You didn't realise mould would be an issue, but there it is, behind the bed, in the bathroom or dotting the kitchen
ceiling. What can you do?
Throughout Australia, landlords have a general obligation to ensure the homes they lease out are in a reasonable state of cleanliness and fit for
habitation by the tenant. As a result, if mould is caused by a leak in the roof, a faulty pipe or gutters or other structural faults, your landlord is
responsible for fixing it and remediating the damage.
That being said, not all mould is caused by structural issues.
- Tenants may be contributing to or creating the problem themselves by failing to regularly
air out and clean the house, allowing condensation to build up in the home, or getting the carpet wet.
- Tenants also have an obligation to inform landlords or their leasing agents if there's a problem with the property, for example a window that doesn't seal
or a leaky pipe.
- If a tenant has caused the underlying problem that led to mould developing, or hasn't informed their landlord of an issue with the property, they could be
held responsible for mould damage and may have to compensate their landlord.
There are still plenty of grey areas, according to Neumeister-Kemp, who often acts as an expert witness in court cases that deal with mould damage.
With no clear-cut responsibility laid out in law, landlords may not accept they're responsible for mould, forcing tenants to go through housing tribunals
or the courts, which takes time and, in some cases, money.
"At the moment, it's up to a judge to decide whether the mould is bad enough and whether the issue is with a building defect and therefore the owner is at
fault," Neumeister-Kemp said. "Real estates don't help at all … The tenant gets hit with fines [for ending a lease early] or having to pay for a
clean up, and the owner gets sued, because the real estate didn't tell the tenant or the owner about a fault like a leaky pipe. Now something that would
have cost $2000 to $3000, becomes a $30,000 to $90,000 claim."
Tips for renters
Before you lease a property
If you notice issues such as windows that don't seal properly, leaky taps or broken gutters, make sure you get your landlord to commit to fixing the issues
in writing before you sign the lease.
While you're leasing a property
If you're already leasing a property and a mould problem develops, try to figure out what's causing it. If it's a small amount of mould in the bathroom or
kitchen, clean it up and air the rooms out well in future. But if there's a significant amount of mould, or you find a leak in the roof or walls, tell your
landlord or real estate agent immediately and ask them to fix it. The longer you wait to tell them, the worse the problem will become – and you could well
be held liable for any delay. Make sure you keep good records of your contact with the landlord or agent and take plenty of photos in case you need them
for evidence later.
If you're not satisfied
If the landlord won't fix the issues or you're not satisfied with the repairs that have been done, you do have some options. You can seek to terminate your
lease early. The landlord may not agree to your request, in which case you may need to go to a tenancy tribunal in your state or territory to
resolve the dispute. If that's the case, make sure you bring as much evidence as possible, including your correspondence history with your landlord or
agent, photos you've taken, and, if you have one, an environmental report on the mould in your home. You can get one from a mould remediation specialist,
or in some cases, from your council.
Case study 1: Emma and Tom*
Emma and Tom noticed a hole in their bathroom ceiling in their home in Petersham, in Sydney's Inner West, in late September. They promptly informed the
property managers, but heard nothing from them for months. Mould started to appear in one of the bedrooms in January, and by late April had spread
throughout the house. In May, with no solution in sight, Tom and Emma, who was pregnant, told the rental agent they wanted to terminate the lease. But the
landlord filed a complaint with the NSW Civil and Administrative Tribunal (NCAT), alleging Emma and Tom had breached their lease. Emma and Tom, who had
kept excellent records of their experience with the agent, filed a counter-claim. Months later, they're in the middle of NCAT hearings.
Case study 2: Amy*
Amy signed a lease on a house on Sydney's lower North Shore. There were signs of problems before she moved in, with some rotting floorboards and walls at the back and foundations of the building. She was told the problem would be fixed before she moved in, but it wasn't. Amy and her children started feeling sick, with respiratory and other issues. She asked a mould remediation expert to test the house. She was told she had a grade 4, or severe, contamination.
Amy asked her landlord to fix the underlying cause of the mould and to pay to have her belongings replaced or treated, but the landlord refused. She filed a case with NCAT, but she received no compensation for the mould-related elements of her claim because the judge said it was impossible to figure out who caused the mould issue. Amy said she spent $96,000 replacing and remediating her personal property, and that a mould remediation expert told her it would cost a further $250,000 to fix the underlying cause of the mould problem in the home. Amy said she is considering filing a civil court case against the landlord.
Does insurance cover mould?
If you own your home and have a problem with mould, there's not much you can do to alleviate the cost of fixing it. Home and contents insurance tends not to cover mould damage, particularly when it's caused by lack of maintenance, such as blocked gutters or missing ceiling tiles. When mould is a secondary
issue that arises as a result of water ingress from flooding, storm damage or burst pipes, you may be covered, according to Neumeister-Kemp. As always, you
should read the terms and conditions of your insurance policy carefully.
Professional mould removal
Surface mould, such as that found on bathroom tiles or on the surface of kitchen cabinets, can be cleaned up fairly easily without calling in outside help.
But if mould covers a large area of your home – according to the Australian Mould Guideline, which was co-authored Neumeister-Kemp, a rough guide
is one metre square – and is dense, or if householders are asthmatic or allergic to mould, it's best to call in the experts.
Professional mould cleaners should be certified, have the right equipment and special training.
While some companies provide initial quotes free of charge, an investigation can cost between $800 to $1500 for an expert to test the site, find the cause
of the mould and write a removal plan. After that, it's a question of the extent of the problem.
If the problem is on the surface – on walls, ceilings or cabinets – it's a relatively simple clean-up job that could set you back a few hundred dollars.
The hourly rate for a mould remediation specialist starts at about $60.
"The actual cleaning of the mould is the smallest problem. If it's just condensation, it's cheap. If it sits on top, it's cheap. For a ceiling, for
example, it'll cost maybe $200," says Neumeister-Kemp. "But if the mould is growing into the ceiling and it's porous, then it's expensive."
Neumeister-Kemp says badly affected homes may have mould behind walls, in and behind gyprock, in ceiling cavities and under carpets and floorboard. Once it
sets into porous materials, it can be easier to replace them entirely than to treat them.
The cost of getting an entire house remediated starts at about $15,000, but can cost much more depending on the size of the home and the furnishings within
it, according to Neumeister-Kemp. The most expensive job she said she's been involved in was a house in Sydney's Bondi, which cost $1.8 million in
DIY mould removal
It's relatively easy to clean surface
Get some rubber gloves and a face mask. If you have a vacuum with a HEPA filter, first vacuum up any visible mould. If you don't, don't try to vacuum or
dry-brush the mould, as this can spread the spores. Next, use vinegar to clear mould from hard surfaces. Pour a concentration of 80% vinegar to 20% water
into three buckets.
Dip a microfibre cloth into the first bucket, then use it for cleaning a patch of mould. Rinse the cloth in the second bucket, then again in the third to
ensure cross-contamination doesn't occur. Vinegar may leave streaks on surfaces, so you may need to use a different cleaning solution to remove
Top tips for keeping your house mould-free
- Keep the temperature in your home even. Try not to let one room get much warmer or colder than the next.
- In winter, have small heaters spread throughout your home rather than one large heater in the centre.
- Never use unflued gas heaters because they can release water vapour into the air.
- Always use the exhaust when you're showering or cooking and open windows when possible.
- Clean up mould as soon as you notice it. Don't let it settle in.
- Wipe up condensation on walls or windows whenever you notice it.
- Keep blinds and curtains open during the day.
- Tell your landlord as soon as you notice a problem and keep a record of any conversations you have over the phone.
*Names have been changed at the request of the interviewees.