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Is Condensation Toxic

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Is Condensation Toxic?

By Ruth MacEachern

Product Manager

Jul 24, 2023

There is a myth that the condensation that forms on windows overnight is toxic and can damage your health if you drink it. This is not quite true. While it is not a clever idea to drink condensation from the window, the liquid itself is just water. That is not to say it would not do you any harm. Any dirt and microbes on your windows will be contained in the water and it could give you an upset stomach.

Condensation itself is not bad for your health, but if it is not dealt with, it can lead to problems in your home that could do actual harm including helping toxic black mould to grow.

Where does condensation come from

Condensation comes from the water vapour that is released during many activities in your home. When you cook or bathe, steam escapes and is carried away by the air. Depending on the temperature of the air in your home, air has the capacity to hold different amounts of water. As the air cools overnight, it can hold less water, and as a result the vapour condenses onto cold surfaces such as windows and walls.

What are the dangers of condensation

If condensation forms on non-permeable surfaces such as glass windows or plastic window frames, it is unlikely to do much harm, and if you wipe it away in the morning, it will not progress further. However, if the condensation settles on surfaces that it can soak into, it can lead to damp patches forming.

If you have a cold spot on your wall or ceiling, it can be a magnet for condensation, and you may not even notice it until it is too late. Moisture can soak through paint and become trapped in the underlying plaster. As the moisture levels build up and the plaster becomes saturated, you may start to notice a discoloured patch spreading on the paint. This is the pigment from the plaster blending into the paint. This damp patch indicates that the underlying plaster has been degraded with moisture. The plaster can begin to crumble, and any paint or wallpaper will start to peel away.

Damaged plaster will need to be replaced. Depending on the spread of damp, this may mean a small patch repair or a larger building job to replace a wall before the room can be redecorated.  It is always better to stop damp before it becomes a bigger problem.

Damp patches also provide an environment for mould to grow. Microscopic mould spores are carried in the air around your home, and most of the time they do not cause any problems. Damp patches can capture the mould and provide it with the nutrients that it needs to grow. Mould grows very quickly, spreading across the surface of the wall to create dark patches, and below the paint making it difficult to remove.

As mould spreads in one location, it starts to release more spores to colonise the surrounding area. These high concentrations of mould in the air can cause an allergic reaction in people with weak immune systems and respiratory conditions such as asthma. Mould spores can also trigger eczema and cause chronic cold like symptoms that last for as long as the mould is present in your home.

Unfortunately, some of the species of mould that grow in British homes release poisonous chemicals called mycotoxins. Stachybotrys Chartarum (toxic black mould) can cause nerve problems and serious reactions in children making it a major health risk.

Some moulds can be removed using a fungicide spray or dilute bleach, but if you suffer from allergies or have found strains such as Stachybotrys Chartarum the mould will need to be professionally treated.

Stopping condensation from causing problems

The only way to stop excessive condensation from becoming a problem in your home and causing damp is to reduce humidity levels. While there are simple changes you can make such as ensuring that kitchen and bathroom doors are closed when in use and avoiding drying clothes indoors, to permanently prevent condensation, you will need to improve the ventilation in your home.

Extractor fans in bathrooms and kitchens can reduce humidity at source – particularly if you choose a modern system such as the EnviroVent Cyclone 7 that detects moisture and runs automatically.

In some cases, upgrading your extractor fans may not be sufficient. Whole house ventilation is more effective. Positive Input Ventilation (PIV) systems including ATMOS improve air circulation throughout your home, gently replacing the stale or humid air with fresh filtered air from outside that is drawn in through a central unit and distributed into multiple rooms.

Find out more

If you have discovered condensation in your home and are concerned about the health risks of mould or damp in your home, we can help. Our local specialists can visit your property and identify the sources of moisture in the air and provide you with advice about the best way to deal with it. Simply enter your postcode below to request a FREE home survey and stop condensation for good.

Need help with condensation, mould or damp problems?

One of our local experts will contact you to learn more about your problems, offer free expert advice and make recommendations for a permanent solution.

During the free survey we will

  • check Assess any condensation, damp or mould problems in your property
  • check Take readings of the relative humidity levels
  • check Identify any underlying problems and make recommendations for a permanent solution

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