Busting the myths about ventilation

11 July 2024

Did you know that, according to Branz (in 2023), around 37% of New Zealand homes have visible mould in the living room and bedrooms. We know that insulation and heating can help provide a healthier living environment, but ventilation plays a key role too.  High moisture levels make your home uncomfortable and unhealthy, and can damage its decor, furniture and even structure. We decided to bust some myths about ventilation and the part it plays in creating a healthy, warm and dry home.


Myth #1 I can just open my windows

Here’s the problem: activities like cooking, showering, and even breathing generate moisture.  And it’s amazing how much.  Cooking can generate 3ltrs a day and doing the dishes generates 1ltr a day. Even just breathing, perspiring and taking showers can have an impact.  If you dry your clothes inside, you will be generating huge amounts of moisture (up to 5ltrs a load). 


Not only that burning incense and candles, using perfumed sprays like deodorants and air fresheners or smoking and vaping indoors reduces indoor air quality.  Without proper ventilation, these pollutants can build up inside, leading to a variety of health issues like respiratory problems, allergies, and even mould growth.


Relying on infiltration or natural ventilation, like opening a window, isn’t really the best option. Some rooms may receive adequate ventilation, others may not. The truth is that you have absolutely no control over the airflow that comes from these sources. Opening the window also doesn’t work is in areas with poor outdoor air quality (for example in the city centre), extreme temperatures, security concerns or high levels of noise pollution.


We breathe in around 8ltrs of air per minute, which totals 11,000ltrs of air per day, so it’s easy to see how fast indoor air pollution could affect our health. Properly installed and ducted ventilation systems continuously remove the moisture-laden, stale air, replacing it with fresher, cleaner, drier air.


Myth #2 It’s expensive

It’s true that installing a ventilation system has an upfront cost.  However, once installed these systems are cheap to run and the benefits are extensive.


Heat and energy recovery ventilation systems typically recover 70 to 80% of the heat in outgoing airstreams and transfer it to incoming airstreams, saving a lot of money in heating the home.


Having cleaner, drier air all year round means a healthier living environment and less illness.  It’s often young children and the elderly who are most affected by living in a damp, mouldy home, but they often require the working members of the family to stay home and look after them when they are ill, resulting in lost income as well as potential long term health issues for the sufferers.



Myth #3 Only people with respiratory problems need a ventilation system

Did you know that damp and mouldy conditions can be major triggers for asthma? But it’s not just asthma sufferers that benefit from a ventilation system.  A constant supply of filtered fresh air entering the home can help to control pollutants in the indoor atmosphere, which can have a positive impact on the health of everyone in the family.

If a home does not have an adequate ventilation system and humidity is high, this can provide a perfect breeding grounds for dust mites. These dust mites and their airborne detritus thrive in homes that are not effectively ventilated.  When their detritus encounters the skin or is inhaled, it can cause allergic reactions, resulting in asthma attacks, eczema, watering eyes, itching, sneezing and a runny nose. These issues can be significantly reduced with an effective ventilation system.

In the summer, hay fever causes misery and suffering for many people. An effective ventilation system can filter out larger particles, such as pollen, preventing them from entering the home. Having a ventilation system in place means there is no need to open the window, which can cause a problem for those with pollen allergies.


Myth #4 There’s nothing I can do about the condensation on my windows

A recent My Health My Home survey found that 58% of homes experience condensation. 


Condensation is most noticeable in winter because there is a large difference in temperature between the inside and outside of the home. That means once the heating is turned off the inside temperature drops quickly and soon reaches the point of 100% saturation. As the air cools further, some of the water can no longer be held in the form of invisible water vapour and begins to form liquid droplets. Condensation is the most common form of dampness and will eventually lead to mould growth.  If it is left to develop over time then damp patches may start to appear on walls, which means that wallpaper may peel, and ultimately black mould will grow. This leads to musty smells, damage to the fabric of the house and it can even result in health problems.


Introducing adequate ventilation gently ventilates the home to transform a stagnant and stale atmosphere into a fresh, healthy and condensation free environment.


Myth #5 Only more modern airtight homes need ventilation


Today’s houses are constructed and designed to seal in the heat (or cool in the summer).  This means the houses maintain a much more stable temperature and energy bills are lower, but it is also making it much harder for them to ventilate naturally.  This means they need a ventilation system.  However, ventilation systems do not only benefit the more modern, airtight homes. 


A typical household produces about 12 litres of water per day from cooking, showering, and general living – the equivalent of a big bucket of moisture sloshing around your home. In addition, our busy lifestyle often means we spend most of our days out and about. That leaves little time to let fresh air in, particularly in cold weather when we often arrive home in the dark and certainly don’t want to fling open the windows then.


At Awarua Synergy our home assessment staff can recommend what is best for your individual home to make the maximum difference with your budget. Each set of circumstances is different – so be sure to chat to our expert team today.


Beat the damp – chat to the expert team at Awarua Synergy today on 0800 WARM SOUTH for your FREE, unconditional home energy health check!

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