A Conversation about Condensation - 21/05/2015

New Zealand is one of the best places on earth to live, but it's always shocking to open our closet and see our favourite jacket covered in mould. We've seen people who had mushrooms growing in the closets, no joke! While we live in an amazing country, some of the houses we’re living in are simply not up to scratch and these unhealthy houses are taking a toll on the people who reside in them. Let’s have a look at the condensation and dampness that’s taking over our homes so that we can figure out how and why it’s important to battle it.

Condensation 101

You already know what condensation is right? You’ve seen it before, on all the windows in your poorly ventilated house. And while you may be thinking that it’s time to replace you’re windows, the problem goes much deeper than that. 

Condensation is the result of your day-to-day activities within your home. With the right conditions, condensation is practically impossible to avoid and will form on any surfaces within your home, but it’s most noticeable on your windows. The worrisome thing is this: that dampness might be everywhere inside your home, not just on those pesky windows.

Here’s how it works: the air we breathe outside contains moisture, and the air inside our homes contains moisture. When the indoor temperature cools the air is unable to hold as much water vapour so then it condenses and becomes visible on cold surfaces, like your windows. While you can see it on the windows and mirrors, what you can’t see is that the same vapour penetrates your clothes, linen, carpets and other absorbent surfaces.

Water, water, everywhere, not a drop to drink

You might not believe me but the average family in New Zealand creates a jaw-dropping 8 litres of moisture in the home everyday. It seems crazy but when you factor is such activities such as cooking, showering and just breathing, it’s a pretty normal amount of vapour to have kicking around your house. Proper ventilation especially through the colder months effectively dries your home removing moisture and dampness.

The worst kind of dampness is caused by moisture coming into your house from outside – particularly from underneath your house if you don’t have underfloor insulation. This kind of excess moisture can be hidden and isn’t detected until, well; you’ve got a closet full of mushrooms you don’t want.  Not only will this kind of moisture damage your house, but it can also reduce its value.  


Wetter is not Better

Unfortunately, in New Zealand 46% of our homes are prone to condensation. This has become such a problem that more tenants are taking landlords to court to fight for their rights to live in a dry and healthy house. Most of these damp houses have mould, and we all know how bad mould is for our health. Dampness makes rooms unhealthy to live in. Here’s how to tell if your house is unhealthy:

The Most Common Symptoms of Excess Moisture:  

  • Rooms that smell musty or rotten
  • Mouldy clothing and shoes in wardrobes and drawers
  • Mould behind paintings, mirrors and posters
  • Watermarks on the ceiling
  • Mouldy ceilings and walls (usually in bathrooms and kitchens)
  • Problem areas of rotting wood in the structure of your house (usually underneath)

If you have one or a few of these symptoms, it’s time for you to do something about your house.

Home Sweet Home?

Here’s the deal – while your house is important, your health is even more so. And if you’re living in poor quality housing, you can bet that your health will be impacted. Cold, mouldy homes hurt your health and your children’s health. Bad homes like these have been linked to cardiovascular disease and the respiratory illnesses that are rampant here in New Zealand. Indoor dampness and mould resulting from poorly insulated and ventilated homes are linked to not only asthma, but serious respiratory infections, and even rheumatic fever.


Indoor dampness and mould is a major trigger for asthma, with 1 in 4 Kiwi kids suffering from respiratory conditions. Taking medication for asthma is more common among Māori children, but it affects all populations living in New Zealand particularly when it manifests in eczema. While it’s a common problem, five children die from asthma complications each year here in New Zealand. That’s five children too many.


Bronchiolitis is another common respiratory infection in infants, and is caused by the respiratory syncytial virus (RSV). Dampness and mould increase the risk of this respiratory infection– which means it’s entirely preventable. Every year one kiwi kid dies from bronchiolitis.


Pneumonia is an inflammation of the air sacs we have in our lungs. It has been proven in multiple studies that dampness and mould increase the risk of this respiratory infection and every year more than 3000 New Zealand children are hospitalised. Pneumonia kills 10 children a year in New Zealand

Rheumatic fever

Rheumatic fever is often caused by an untreated sore throat, and leads to rheumatic heart disease, which requires surgery to save the person afflicted. New Zealand has some of the highest rates of rheumatic fever in the developed world which is simply an embarrassment for our nation.

Eyes Wide Open

We don’t want to make you paranoid, but keep your eyes peeled for mould at all times. If you catch some spores, clean that mess up, STAT. It’s often lurking in hidden areas like wardrobes, under carpets and behind curtains and furniture. Once you find it, remove it by spraying with white vinegar, let it sit a while to kill the nasties, then wipe the area with a clean cloth, soap and water. Throw away the cloth afterwards as mould can live on in damp surfaces. Removing mould is a short term solution; for long term results it may be time for you to invest in a proper ventilation system for your home.

Family -condensation

Not only is it a wise investment for the health of you and your family, but the installation of a ventilation system will only make your house worth more money when you decide to sell it. With the proper insulation combined with good heating sources and a ventilation system, your house will be an oasis from our wet and windy winters.

You should talk to our experts about how ventilation is key to managing the amounts of moisture you produce in your home from everyday activities. Not only can we provide you with the proper systems, we can also take a look at your house and find out exactly what the problems are.

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