What is Condensation?

Air will contain varying quantities of water vapour depending on it's temperature, with warm air holding more moisture than colder air. Condensation occurs when humid air comes into contact with surfaces that are colder than the humid air surrounding them.

As the temperature this warm/humid air falls, so does the amount of moisture it is able to hold. The temperature of the 'excess' moisture lowers nearest to the source of cold, forming droplets of water. This condensation is most noticeable when it forms droplets or beads of water on hard/non-absorbent surfaces, such as windows or tiled walls.  Condensation can form on any surface, however this may not become apparent until a mould becomes noticeable.

In colder climates, such as the UK, condensation is predominately a winter problem. This is most apparent in kitchens from boiling water and bathing/showering in bathrooms. While the general heat from kitchen appliances such as ovens will have a drying effect on the room, bathrooms tend to remain unoccupied most of the time, are cold and unventilated when not in use.

Mould, Mildew and Condensation

The use of the terms condensation and mould are frequently confused. Condensation is water, or the action that  causes airborne water to appear on surfaces. Mildew grows on fallen leaves in autumn. Mould is a type of fungi.  Mould spores are everywhere around us; In the air, on furniture, in our cars, even on our clothes in our hair! Mould is a useful part of nature and plays its part in the scheme of things. Usually there isn't sufficient humidity or food (organic matter) for the mould to become a nuisance inside our homes, but mould spores thrive in humid (over 46% humidity) environments and soap/shampoo residue, wet plaster or floorboards from leaking plumbing or even microscopic particles from cotton towels and human skin are ideal 'food' for mould.

Easily addressed condensation problems:

Common causes of humidity in the home:

Simple responses: