Understanding Condensation and how to prevent damp conditions in your home
We all have water inside our homes, it is a useful part of everyday life. Normally this is not a problem as it is contained by pipes, faucets, and taps and restricted to rooms designed to handle it like bathrooms and kitchen.
However, excess and uncontrolled water can and will cause problems inside your home, dealing with a leak is an easy if not unwanted task.
However Condensation inside your home can creep up slowly and become a long-term issue and if it is not treated properly will lead to damp and mold issues, causing damage and ill health.
Understanding what condensation is and how it forms will allow you to better prevent it from causing issues and any damage.
Here is my guide to help you understand and deal with condensation in your home.
What is condensation?
The Air inside your home carries moisture in the form of water vapour. The amount of water vapour it can hold changes with an increase in temperature and pressure, for warm air has the ability to hold more water vapour than cold air.
Condensation occurs when warm moist air contacts a colder surface, and cools down to the ‘Dew point’ at which water vapour condenses to form water droplets on the cold surface, these water droplets are known as condensation.
As the temperature of the air increases, it expands and is able to absorb more moisture, acting a bit like a sponge pulling moisture in as it expands
When warm air, which has a high moisture content. meets a colder surface like brick or glass, the air cools and contracts until it is no longer warm or big enough to hold the water it has absorbed and in the same way as a sponge behaves when it is squeezed, the air condenses, depositing water in liquid droplet form on the cold surface.
The temperature that this transformation happens is called the ‘Dew point’.and this will vary depending on the pressure and the humidity of the local area.
The water droplets that are formed are known as ‘condensation’ and if left to accumulate on the surface, can then cause all sorts of problems inside your home.
Conditions for creating condensation:
In a modern home moisture vapour is produced by everyday tasks like boiling water when you are cooking, using warm water for washing, taking a shower, or having a bath, this means that your kitchen and bathroom are going to have the highest levels of moisture, as you would expect.
But even the simple act of breathing creates moisture, as we inhale, we bring cooler, dryer air into our lungs, and when we exhale we expel warm moist air which is released into the surrounding area,
This means that at night bedrooms can become full of moisture which then comes into contact with windows and walls, thus causing condensation.
The air inside your house is normally warm enough to hold moisture without reaching saturation point or Dew point – but in cold weather, the low temperature outside cools the external walls and windows below the temperature of the heated air inside.
When this happens the air condenses and water droplets form on the cooler surfaces like window panes, walls, and doors.
If there is enough moisture it can and soak into the coverings, like wallpaper, the plaster and wooden terms, and even the furniture.
During the cold winter months, this process is made worse as we often keep our windows and doors closed which prevents any fresh air from entering into the house and replacing the humid air, before it can condense.
What causes Damp inside your home?
The cause of Damp conditions inside most new houses is usually due to condensation created by the effects outlined above which are left untreated long enough for the moisture to soak into the building structure.
The cause of condensation inside a modern home is usually a result of a combination of changes in air temperature, excess thermal insulation, high humidity, and poor ventilation leading to high levels of water vapour.
Often dealing with one of these problems in isolation can result in the condensation appearing elsewhere or even make the symptoms worse rather than fixing the problem.
Simple ways to help reduce condensation
There are many ways to reduce the build-up of moisture in your home which can help prevent more serious issues like dampness and mould from occurring, here are a few suggestions:
- Regularly open windows to allow fresh air into your home, regularly changing the warm damp air inside your home with fresh cooler air will help remove water vapour and reduce conditions that can cause condensation.
- Try to do this on a dry day rather than a wet and rainy one to avoid allowing in the more damp air.
- Use Extractor fans in High-risk areas like Kitchens and bathrooms, good quality extractor fans will help pull away damp air removing the moisture held inside it.
- Look to fit a unit with the highest throughput available, this will be shown as a volume in cubic feet per minute (CFM) or meters cubed per hour (m³/hr).
- Sleep with a trickle vent or small window open, this will allow a regular change in the fresh air whilst you sleep, removing the vapour from your breath and helping to prevent condensation.
- Use dehumidifiers to dry out rooms, these units come in several sizes and can help to remove excess moisture from your home.
- Dry wet clothing in well-ventilated rooms, to avoid the moisture from the clothes creating damp conditions inside, try to remove as much moisture as possible by spinning at a high RPM before hanging out the clothing.
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This article was written by: Richard Quinton – The DIY Help Desk Owner, Engineer & technical specialist.
Richard is one of the key partners in The DIY Help Desk team. He is a qualified Engineer, writer, and publisher, educated to Master’s level. He is a keen advocate of DIY and home improvements.
Richard enjoys helping others to learn new skills and reach their goals and believes that passing his knowledge and experience on through his writing is an effective way to positively impact the lifestyles and well-being of others on a larger scale.