What Is Condensation?

Condensation is the transformation of water from a gaseous state (water vapour) to a liquid state (water). Warm air rises, cools, and loses its ability to contain water vapour, resulting in condensation in the atmosphere.

When warm air full of moisture comes into contact with a cooler wall or window, the warm air is unable to maintain the same quantity of moisture, and the water is discharged onto the cold surface. This can also happen when warm air and cold air meet, causing condensation to develop.

If the temperatures remain warm and moisture is not dealt with promptly, mould will develop. When the temperature inside the home falls, especially at night when the heating is switched off, this happens in thousands of houses across the UK.

When the air can no longer retain all of the moisture that we make in our houses, it migrates to the coldest surfaces in our homes, such as windows and walls, where it condenses.     

The Different Types of Condensation

Surface condensation is the most common sort of condensation, and it manifests itself as water on window glass.

Cold Bridge Condensation develops when warm, moist air comes into contact with surfaces at or below their dew point.  This often happens at the base of external walls.

Warm-front condensation happens when moist, warm air enters a cold environment.

Interstitial Condensation is caused when warm, wet air diffuses into a vapour-permeable substance, such as fibrous insulation.

Reverse condensation or summer condensation happens when rain soaks a wall and then the sun dries it, the heat may actually drive water vapour into the wall.

Radiation condensation or clear night condensation is a kind of condensation caused by radiation. Condensation can form on the underside of roof coverings if the temperature drops suddenly at night.

Signs of Condensation

You can easily see the signs of condensation in your home and these include:

• Streaming windows
• Wet walls
• Damp areas on walls
• Peeling wallpaper
• Signs of mould growth
• Musty smell on clothes in wardrobes

Condensation is the most common type of damp, and it can contribute to the development of mould. When the temperature dips below the temperature of the moist air within the property, it forms on inside surfaces. Keep an eye out for condensation, since it may lead to an unattractive, musty property if left unattended. Also, it has the potential to trigger or cause health issues such as asthma and other disorders.

Many people are used to waking up to condensation on windows, especially in the winter, and this is generally the first indicator of a condensation problem. If condensation happens for an extended period of time, further symptoms such as moist patches on walls, peeling wallpaper, and eventually black mould growth will develop.

Do you know what interstitial condensation is?

Interstitial condensation occurs when wet air reaches the concealed area within an enclosed wall, roof, or floor cavity structure, causing structural damping. When moisture-laden air reaches a dew point temperature layer inside the interstitial structure, it condenses into liquid water.

In warm outdoor temperatures, moisture-laden air can penetrate into the buried interstitial wall cavity from the outside, and in cold outdoor conditions, it can penetrate from the inside. The consequent structural damage, as well as mould and bacterium development, may go undetected on the surface until considerable damage or widespread mould and bacteria growth has occurred.

These effects can lead to musty smells, damage the fabric of our homes and can even affect our health causing asthma and other respiratory problems. Don't let condensation problems ruin your health and home, contact us today to arrange a free home survey.

Need more advice? Read our  14 top tips to reduce condensation in your home.