For most people, home is a sanctuary. It’s a safe space, where we relax and feel completely at ease.

But what happens when your home is making you sick?

The most common cause of house-related illness is poor ventilation. Inadequate ventilation causes mould and mildew, which can trigger a range of respiratory disorders including asthma, skin problems, and ear, nose and throat irritations. Respiratory problems including asthma are of particular concern for young children, the elderly and people with compromised immune systems.

The emergence of mould should be considered a warning sign about the well-being of a building and a trigger for an investigation of any underlying problems. Mould can be a sign of serious leaks, rising damp, or ventilation problems.

The Australian Institute of Architect’s Ask an Architect service estimates that 70 per cent of mould problems are due to condensation from wet areas like bathrooms and laundries, while 30 per cent comes from rising damp. This means that the good news is that for most properties, mould can be prevented by homeowners and tenants following some basic principles:

1. Always use extraction fans or open a window when showering, cooking or using a tumble dryer.
2. Unflued gas heaters can produce up to one litre of water per hour and are also associated with an increased incidence of asthma. Consider replacing unflued gas heating with alternative heating that does not emit moisture, such as flued gas heating or reverse cycle air conditioning.
3. Open windows when practical to reduce condensation build up.
4. Repair any leaks in the roof or pipes.
5. Avoid having piles of clothing or damp towels on the floor (a common problem in homes with teenagers!)

If it’s too late for mould prevention, thankfully there are effective methods for killing mould spores and cleaning the home and its contents. For families with asthmatics and other health conditions, it is always worth trying less aggressive and more natural cleaning strategies first to avoid introducing additional irritants to the home’s air. Ask an Architect recommends white vinegar for cleaning mould, at a ratio of 80 per cent vinegar to 20 per cent water. Properly diluted clove oil or tea tree oil can also be effective, but may cause an allergic reaction in some people.

Many people also use bleach-based cleaning products, but be aware that most commercially available bleach-based mould cleaners are at an inadequate concentration to be effective and instead only act as a masking agent, bleaching the colour from the mould spores but not actually killing them. Bleach also can also erode the grout between tiles, further contributing to dampness problems.

If mould is a consistent problem in a home, there are a range of professional services that can be enlisted to help:

• Consult an architect to identify opportunities to improve the air flow and ventilation in a property – especially if you are considering renovating or rebuilding.
• Ventilation specialists should be consulted for sub-floor and in-roof systems that can help make the air in a home drier and filter out a range of pollutants and allergens including dust mites and mould spores.
• Consult damp control specialists, especially for rising damp issues, to investigate options for repairing or replacing the damp-proof course, repairing leaking plumbing and improving sub-floor ventilation.
• Consult mould cleaning specialists for extensive or persistent mould problems.

To a certain extent, mould is part of life and to be expected, especially in humid and temperate climates, or during cold and damp times of the year like autumn and winter. However, serious and persistent mould is unhealthy and should not be tolerated. Homeowners need to be encouraged to take action to resolve ventilation and mould problems, and to seek professional help if DIY approaches do not help with rectifying the situation.