Controlling moisture build-up

Controlling moisture build-up

Moisture accumulates in the house from people bathing, showering, cooking, breathing, and watering plants. It also comes into a home from outside. Some appliances, such as unvented gas heating, clothes dryers, dishwashers and washing machines also produce excess moisture into the air.

The moisture builds up quickly and is worse in modern homes which are built to be almost airtight. On cold days you can see the moisture when it collects on the windows as condensation. It is also absorbed into fabrics and building materials. The problem with this moisture build-up is that it can cause mould and mildew on walls and fabrics, which is not only unsightly, but can trigger allergies. For example, dust mites - the source of one of the most powerful biological allergens - thrive in damp conditions.

If you are building a new house, there are a number of chemicals and resins present in many building materials which continue to leak into the indoor atmosphere for many months after you move in. This can be managed with good ventilation.

The options for managing moisture are:

• Good ventilation.
• Window joinery with built-in drains - that allow condensation to drain to the outside.
• Keeping the house warm and dry through heating.
• Extraction fans in bathrooms and kitchens.
• Good insulation to keep the home warm and reduce condensation and mould growth.