Moisture refers to the presence of a liquid, especially water. Small amounts of water may be found, for example, in the air (humidity), in foods, and in various commercial products. Moisture also refers to the amount of water vapour present in the air. This is the moisture that we are interested in dealing with to create a healthy home.
Water is present as a liquid – for example rain, puddles, rivers and oceans - and as a gas in the atmosphere. When water is a gas, it is called water vapour. You will be aware of water vapour when you breathe out on cold mornings or see a ‘mist’ on a river or lake. It’s also called clouds when you look up into the sky. Water vapour is created in your bathroom when showering.
Many people conveniently call water vapour ‘steam’. That’s not technically correct as steam is water vapour at 100 degrees C – as it flows out of the boiling kettle.
Humidity is another common but confusing term. Humidity is the amount of water vapour in the air. Water vapour is the gaseous state of water and is invisible until it condenses. Humidity indicates the likelihood of precipitation (rain), dew, or fog.
There are three main measurements of humidity: absolute, relative and specific. It is a little complex to explain these here but if you are interested just ‘google’ them – it’s very interesting.
When you breathe out on a cold morning, the warm moist air from your lungs hits the cool air outside and condenses to become visible. The vapour on a river exists because the temperature of the water is warmer than the air temperature so again, visible vapour is formed. This is the same effect in your bathroom shower. Warm moisture laden air rises up in the shower to join the cooler air in the bathroom. That becomes visible vapour – which in turn condenses onto any cooler surfaces like tiles, mirrors or windows.
In your home, water vapour is created by breathing, cooking, drying laundry, showering and in many other ways. The warm air in the home holds the moisture invisibly until it touches a cold surface, like a window. It then condenses back to a liquid.
Water vapour and condensation, collectively called moisture, feeds moulds and mildews and makes drapes, carpets, bedding and clothing damp. Damp is cold. Damp and cold is unhealthy.
Keeping your home warm with insulation and adequate heating is very important. It is easier and cheaper to have a healthy home, if it is well ventilated by fresh dry air. An Unovent® home ventilation system will provide that air which is conveniently and inexpensively taken from the ceiling space in your home and blown throughout various rooms in the house.