What Is Condensation?

Condensation is the change of water from its gaseous form (water vapor) into liquid water. Condensation generally occurs in the atmosphere when warm air rises, cools and looses its capacity to hold water vapor. 

In regards to condensation in your home, when warm air which is full of moisture comes into contact with a wall or window, that is colder than it is, the warm air is unable to retain the same amount of moisture, and the water is released onto the cold surface, this can also happen when warm air and cold air meet, causing condensation which is visible to see to form.

This is quickly followed by mould if the temperatures remain warm and condensation is not dealt with immediately. This happens in thousands of households across the UK when the temperature drops inside the home, especially at night time when the heating is turned off. 

The air reaches the point where it can no longer hold onto to all the moisture that we create in our homes, and it migrates to the coldest surfaces; the windows and walls, where it appears as condensation.

The Different Types of Condensation

Surface condensation - This is the most familiar type of condensation, taking the form of water on window panes.

Cold-bridge condensation - This occurs when warm, moisture-heavy air comes into contact with surfaces at or below its dew point. This occurs at the base of external walls.

Warm-front condensation - This occurs when warm, damp air gets into a cold house.

Interstitial condensation - This happens when warm, moist air diffuses into a vapour-permeable material, such as fibrous insulation. 

Reverse condensation - This is also called “Summer condensation”. If rains drenches a wall and strong sunlight then dries it, the heat can actually force water vapour into the wall. 

Radiation condensation - This is sometimes called “clear night condensation“. If there is a sudden temperature drop at night, it can cause condensation on the underside of roof coverings.

If your home is suffering from condensation you will start to see signs of it very quickly which include:

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

Condensation is arguably the most common form of dampness and can eventually lead to the growth of mould. It builds on internal surfaces when the temperature drops sufficiently below the temperature of the moist air inside the property. You should watch out for it because if left to develop, condensation can lead to an unsightly, musty property. Moreover, it can also aggravate or trigger health problems such as asthma and wider complaints. 

Waking up to condensation on windows is a familiar sight for many people, especially in winter and this is usually the first sign of a condensation problem. If condensation occurs over a prolonged period, other symptoms will start to appear such as damp patches on walls, peeling wallpaper and ultimately black mould growth.

Have you heard about interstitial condensation?

Interstitial condensation creates structural damping that occurs when moist air penetrates inside the hidden space within an enclosed wall, roof or floor cavity structure. When that moisture laden air reaches a layer inside the interstitial structure that is at dew point temperature, it will condense into liquid water.

The moisture laden air can penetrate into hidden interstitial wall cavity from the exterior in warm outdoor temperatures and inside the building during cold outdoor temperatures.  The resulting structural damage, along with mould and bacteria growth may occur without any visible surface indications until significant damage or extensive mould and bacteria growth has occurred. 

One manifestation of interstitial condensation might be mould growing on the inside wall surface. Mould due to interstitial condensation might be distinguished by being over an entire surface instead of confined to a corner of the room. A building inspection, when a property is being sold, might also discover rot inside the building structure.

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 latest blog post and get 14 top tips to reduce condensation in your home.