What You Need to Know About Condensation

What You Need to Know About Condensation

By Ruth MacEachern

Product Manager

Condensation is an issue in one five UK households.  Although it might seem to be a minor inconvenience, if it is not properly dealt with, condensation can lead to major damage to your property through damp and can even lead to health problems if it develops into mould.  Understanding what causes condensation means you are better able to prevent it.

What is condensation?

Condensation is caused when warm, moist air comes into contact with a cool surface such as a wall or window.  At different temperatures, the air can hold different amounts of water, and as the air cools, the amount of moisture it can hold drops.  When the air temperature decreases below the dew point, the water in the air is deposited in the form of droplets on the cold surface – this is condensation.

Where does water vapour in the air come from?

Moisture is released into the air during many different activities in the home.  Bathing and cooking are the most obvious sources of moisture, but drying clothes on radiators, using washing machines and tumble driers, and even breathing release water vapour and contribute to higher levels of humidity that can lead to condensation.

What Are the Different Types of Condensation

Did you know that there are actually multiple different types of condensation that are present in your home?

Surface Condensation

Surface condensation is the type of condensation that you will be most familiar with, as it is the most visible.  It takes the form of droplets of water on windowpanes, cold wall surfaces and tiles.

Interstitial Condensation

If surface condensation is the most obvious type of condensation, Interstitial condensation is perhaps the least known.  It is caused when the moist air diffuses into a permeable material like insulation.  If the material is warm on one side and cold on the other, the moisture will be deposited in liquid form and become trapped in the insulation where it can quickly lead to the growth of mould.

Summer or Reverse Condensation

Reverse Condensation is most often seen after heavy rain in the summer.  Rather than forming inside your home, it forms inside the walls when the sun causes rainwater to evaporate.  It forms on the outside of your insulation and can lead to patches of mould and damp inside your walls.

Cold-bridge Condensation

Cold Bridge Condensation is similar to surface condensation, but forms in slightly different places such as the underside of your roof and low down on walls.  It might be mistaken for rising damp and causes many of the same problems including causing windowsills to rot.

Radiation condensation

Radiation condensation most often forms on clear nights when the temperature drops quickly.  This type of condensation forms on the underside of roofing material and then drips onto insulation in your loft where it can develop into damp and cause mould to grow and release spores into the air of your home.

Warm-front Condensation

You will often find warm front condensation unheated and unoccupied houses.  It often occurs I the winter during warmer periods and is caused by warm, moist air from outdoors being trapped in a cold building in the absence of other sources of moisture.

Where Can Condensation be Found?

Condensation can form on any surface that is cooler than the ambient air but is most obvious to see on windows and tiles where it will form beads of water as it cannot soak into the surface.  On porous surfaces including wood and even soft furniture, where the moisture can soak through the surface, condensation is more likely to cause bigger problems like damp and mildew.

Why Condensation is a Problem?

In the long term, condensation causes multiple issues in your home.  The most obvious result of condensation is damp.  You may see patches of black mould develop around windows or your ceilings.  Damp can cause a number of health problems for residents including worsening asthma and allergies due to the presence of dust mites and mould spores in the air.

As well as the health risks, long term damp can also cause damage to the fabric of your home.  You may notice crumbling plaster, peeling wallpaper, and stains on paint that can be expensive to fix.

How You Can Prevent Condensation

Adequate ventilation is the most effective way to prevent condensation in your home.

Simple extractor fans in bathrooms and kitchens reduce the amount of humidity effectively and help to stop water vapour escaping into other parts of your home where it might settle as condensation.

A modern whole house ventilation system can protect your whole house from condensation by drawing fresh air into the building from outside which will force the humid air outside where it can’t do any harm. 

To find out how EnviroVent can help you improve indoor air quality and reduce condensation, please contact us today to book a free survey – simply fill in your postcode below to find your local ventilation specialist.