Dehumidifiers - one of my favourite things
Updated: Apr 1, 2019
One of my top recommendations when doing a Building Biology Assessment is to get a dehumidifier. I can’t tell you how many times my dehumidifier has gotten me out of a jam.
Whilst I live on the Northern Beaches of Sydney where we get our fair share of humid days, I don’t use it to reduce humidity levels in my house. My home is north facing and gets good cross ventilation, so I am fortunate not to wake up to new coloured wall paper. My dehumidifier is used to make sure I don’t have damp piles of ‘stuff’ brewing up a few million spores of aspergillus or penicillium or some other nasty mycotoxin producing species of mould.
My family is constantly finding new ways to use the dehumidifier....
Rain soaked school bags; soggy shoes; damp camping gear; favourite book that was in the rain-soaked school bag. All these items (bar the book that took 2 days of drying) were dry within hours when huddled in my laundry with my trusty dehumidifier. Because of course these events happen when it rains for days on end with no hint of the sun, my normal go to for drying.
I have also dried out carpet that got wet during a storm; the shower recess when we replaced silicone; the laundry when the washing machine leaked; the bathroom when the bath overflowed. If something can flood or leak …it generally does, and I have dried it out! The thing is, once anything is left wet for more than 48 hours the risk for fungal activity is high. My dehumidifier has literally saved me thousands of dollars in repairs and replacement costs, not to mention the potential cost to my family’s health.
By far the most common use is to dry school uniforms overnight and I am always using it to dry clothes that I don’t want shrunk in the dryer on rainy days. Drying clothes indoors without a dehumidifier means all that water goes straight into your home.
I have the Ausclimate 35 Litre All Season’s dehumidifier which works in both warm and cool climates. It does create a bit of heat when closed in my small laundry, so maybe not the first choice to use in a hot climate to reduce humidity. In fact, over summer the best way to reduce internal humidity is to turn on the air conditioner as it pulls moisture from the air as it cools. I know, the healthy home is not always the energy efficient home.
There are two types of dehumidifiers – refrigeration or desiccant. Refrigeration dehumidifiers work by condensing moisture out of the air and work well in warm climates. Desiccant dehumidifiers work best in cooler temperatures as water is removed via an adsorbent desiccant material that is then heated so that the moisture can be vaporised out of the building.
A good dehumidifier can do a deep-down drying of a room. Shut the dehumidifier in the room for 1 to 3 days and set the thermostat to 30% RH (or the lowest level available on your model) as this will allow the unit to run continuously. You will have to empty the tank as it fills and when it takes longer to collect less water you know the room has reached maximum drying. This is great if you have a room that has no windows or has issues such as rising damp that you have yet to repair. You can then do a maintenance program, running the dehumidifier on an intermittent basis depending on the conditions.
Choice Magazine recently did a review of dehumidifiers (the Ausclimate models were not reviewed) and this is their top 5.
1. Ionmax ION632 (80%) 2. Cli-Mate CLI-DH8D (74%) 3. Ionmax ION612 (73%) 4. DeLonghi DDS30 (68%) 5. Dry Home DH24 (62%)
If you find you have rooms that feel damp or have a musty odour, then a dehumidifier is a great investment. However, if you find that your dehumidifier is filling up every day without fail, then you do need to look at why this is so. Stopping moisture at its point of entry is always the priority. If you are renting, then maybe it’s time to hit the real estate pages and look for a new home that is high and dry! If you own, then investigate solutions to protect your investment. A building biology assessment can help you identify the underlying issues…but until then a dehumidifier is a very handy tool.