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Does Condensation Damage Your Health

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Does Condensation Damage Your Health

By Ruth MacEachern

Product Manager

Sep 18, 2023

As we move into the autumn, seeing condensation on windows in the morning becomes more common.  Cooler nights mean that there is a bigger difference between the internal and external temperature which creates cold patches around windows.  In these cold spots, the air cannot hold as much moisture and deposits the vapour that it carries onto the panes of glass to create visible condensation.

Many people worry that the presence of condensation on their windows each morning can be bad for their health, and while there is some truth in that, it is a bit more complicated.

What is condensation?

Quite simply, condensation is water.

During the day, we release a lot of moisture into the air of our homes.  Activities such as cooking, bathing, and even breathing release small amounts of water vapour into the atmosphere, and this is carried around the house.

Air has a surprising capacity to hold moisture – at room temperature (20C), a cubic metre of air will contain approximately 17g of water.  At night, as the temperature drops in your home, the amount of moisture that the air can hold falls.  At 15C, the air can hold approximately 13g of water.  In a typical bedroom 32m3 in size, his means that 128g of water will be released – a small glass full.

This water is released by the air onto cold surfaces – windows and exterior walls where it can pool and be seen as condensation.

What are the health risks of condensation?

Because condensation is just water, it is quite safe.  If it is allowed to stand for too long, it can become home to bacteria, but in most homes, the water will simply evaporate as the temperature rises during the day.

Condensation is however a cause for concern because of the issues it can cause in your home – namely damp and mould – which are more of a risk to both your property and your health.

Mould grows from microscopic spores that are carried on the air around your home.  These tiny spores are everywhere, and until they meet a moist surface, they are inert.  In low concentrations, they are barely noticeable, but in the damp patches that develop from untreated condensation, they can quickly activate and start to grow into large colonies that spread in dark patches on walls and ceilings.

As mould matures, it releases more spores into the air, and this is where the health risks arise.

Mould spores are an allergen for many people.  They can cause irritation of the airways and affect breathing for people with respiratory conditions such as asthma.  Other common allergic reactions to mould spores include skin and eye irritation, and in some cases, they can also affect brain function.

There are many thousands of different mould species that are found in a typical home, and some of these are release chemicals called mycotoxins that are extremely bad for your health.  Toxic Black Mould (Stachybotrys Chartarum) is commonly found in UK homes and needs to be professionally removed.

Read more about stopping mould >>

Stopping Condensation

To avoid the risks of damp and mould in your home, it is important to reduce humidity levels.  There are simple steps you can take including ensuring that you use lids on pans while cooking, waiting until your dishwasher is cool before opening it, and avoiding using radiators to dry towels and clothes, but ultimately, the most effective way of stopping condensation for good is through improving the ventilation in your home.

Read more about reducing condensation >>

How ventilation stops condensation, damp, and mould

Improving the ventilation in your home will help to reduce humidity and prevent condensation.  Bathroom and kitchen extractor fans work by drawing moist air out of the house quickly in the areas where it is most likely to build up.  Modern home extractor fans such as the EnviroVent Cyclone 7 feature humidity sensors that detect the amount of water contained in the air and adjust their power levels to speed up the process.  This means that the water vapour has less chance to migrate to other rooms where it can cause condensation and damp.  Automatic extractor fans are highly efficient because they work more quickly and use less energy than older designs.

If you find that condensation is a problem in areas away from sources of moisture, whole house ventilation systems may be more effective.  Positive Input Ventilation Systems (PIV) such as Atmos work by drawing fresh air into your home from outside to displace the humid air.  These systems feature a central unit in your loft and gently distribute fresh air throughout your home.  Positive Input Ventilation runs 24 hours a day and helps to maintain even temperatures throughout your home and reduces the presence of some allergens including pollen and mould spores from building up.

Find out more

If you have discovered condensation on your windows and are concerned about the potential risks of damp and mould, we can help.  EnviroVent have ventilation experts across the UK who can visit your home to carry out a FREE home survey.  This survey will identify the causes of condensation in your property so that you can find the best way to deal with it.  For more advice, please enter your postcode below to find a specialist near you.

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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