Controlling condensation

If you've got a problem with condensation, the first thing you need to do is consider where the water is coming from. Here are some of the common problem spots.

Sources of moisture

Want to check the humidity in your house?
Inexpensive ($12 plus freight) humidity gauges are available that let you check humidity levels in your house – useful for finding the sources of dampness. See www.thermometer.co.nz.

Improving condensation problems

• Keep rooms ventilated and warm during winter - at least 7°C warmer than outside temperatures. Install heavy curtains and draw them at night: it helps keep the home warm and reduces the number of cool surfaces for water vapour to condense on. Leave windows closed on damp days.
• Dehumidifiers have often been teamed with unflued LPG heaters. One spews out moisture (and other contaminants) while the second mops up the moisture. No, no, no. It’s not the dehumidifier that’s the problem here – it’s the unflued LPG heater. Their exposed flame is a fire risk and they fill the house with water and other harmful contaminants. Don’t use them. Use cheaper to run and safer electric heaters.
• Always use close fitting lids on pots when cooking and fit extractor fans over the cooktop or stove, and in the bathroom (these must be ducted to the outside).
• Use a cupboard heater in problem wardrobes. A ventilation grille in the top of the wardrobe will also help.
• Vent clothes dryers to the outside and don't hang clothes inside to dry. Close doors when cooking, showering or using the dryer, to limit the spread of moist air.
• Limit the number and size of pot plants in the house, .
• Check the ground under your house is dry. If it's wet, cover with polythene (if feasible), taping the joints, and ensuring a tight fit around piles. Check that drainage systems are diverting water away.
• Fix any leaks in the roof or around windows.