This is how you can reduce the humidity in the bathroom

Everyone knows it - after showering or bathing, there are always foggy mirrors and high humidity, which is recognisable by a foggy haze of water vapour in the air. This happens when water condenses, as well as, for example, when our bodies are in motion and we sweat. In the bathroom, however, condensation has much greater proportions and can bring negative effects.

If this is the case, it is important to lower the humidity of the air in the bathroom to effectively prevent mould growth and thus prevent damage to your respiratory system, general health and your bathroom. The grout, tiles or walls are particularly susceptible to mould when the humidity is high!

There are numerous methods to lower the humidity in your bathroom. If your bathroom has a window, for example, it is always worth ventilating well after a bath or shower to let excess moisture escape and fresh air in. But there are also effective ways to reduce high humidity in a bathroom without a window.

In the following article, you will find information on how to determine the humidity levels in your bathroom, what the optimal room humidity is and what tips you can use to best reduce the humidity content of the air in your bathroom.

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Why is optimal humidity in the bathroom important?

What is the optimal humidity in the bathroom?

The optimal humidity level in the bathroom is between 50-70% (in other rooms of your home it is between 40-60%). When you shower or bathe, a lot of moisture often escapes into the air. This causes the humidity in your bathroom to rise abruptly to a value of about 80%.

The problem with this is that such high room humidity creates damp areas, as the warmer, more humid room air cools down on the colder tiles at low room temperatures and seeps down in the form of water. If these areas are not always dried off in the long term and increased humidity remains in the bathroom, mould develops.

Especially in places such as new buildings, hotels or older houses, the bathroom is often designed without windows, which can have a very negative effect on the indoor climate and on the indoor humidity.

However, the problem of increased humidity in the bathroom after showering can be quickly solved by sufficient air exchange.

Measure the humidity using a hygrometer

To find out how high the humidity is in your bathroom, you should not rely on guesswork. It makes more sense to get yourself a so-called hygrometer.

With a hygrometer, you can measure the humidity in your bathroom or other rooms. The value given by the measuring device describes how high the air humidity is. With the help of this value, you can find out whether you have sufficient air exchange in your bathroom or whether you need to resort to other ventilation mechanisms.

Hygrometers are available in both digital and mechanical models - so there is a suitable device for controlling the indoor climate for every bathroom!


Reducing humidity - but how?

In bathrooms that are equipped with a window and border on rooms with a dry indoor climate, it is often sufficient to open the window after showering or bathing to ensure an exchange of air and to lower the humidity.

Here, it is important to create a draught by opening the window and door.

In addition, even if there is sufficient air exchange, it makes sense to remove excess water from the tiles and grout with a tile remover or a cloth and dry them.

But what if the bathroom only has a small window or no window at all?

We at DUSCHKRAFT have the solution. With the help of our bathroom dehumidifiers, you will never have mould in your bathroom again!

Reducing high humidity in the bathroom without windows

Interior bathrooms in particular usually only have passive ventilation systems: The air exchange takes place via an opening to a ventilation shaft.

However, these are not sufficient to ensure adequate air circulation. Another method must be resorted to in order to reduce the moisture content of the room air.

Installing a deaerator

Decentralised ventilation system for bathrooms with an external wall: For bathrooms without windows, a decentralised ventilation system is an effective alternative. A decentralised ventilation system draws the humid air outside and lets fresh air flow inside the room.

A decentralised ventilation system is particularly practical because it can also be retrofitted into a flat and no extra exhaust pipes have to be installed.

  • Mounting: Bathroom vents are mounted quickly and without great effort on an exterior wall of your building. All that is needed is a core drill hole or a wall opening to create a duct for the air exchange.
  • Function: A decentralised ventilation system works with the help of a small fan, which creates a negative pressure in the room and thus extracts the humid air from the bathroom. The moisture stored in the air is thus transported to the outside - the humidity levels in the bathroom drop. At the same time, fresh outside air flows into the bathroom through the ventilation slits or flaps, which has a positive effect on your well-being and the room climate.


Tips you should consider when buying:

  • Heat recovery: When buying a decentralised ventilation system, you should make sure that it has a heat recovery function. By extracting heat from the exhaust air, the ventilation system can heat up the incoming fresh air - so the room temperature remains constant. Up to 90% of the heat is thus retained, which means that you do not have to fear higher heating costs because the room temperature is too low, despite the inflow of outside air.
  • Controlled ventilation: Another aspect you should consider when buying a ventilation system is that you buy one with controlled ventilation. In such models, sensors measure the temperature and humidity values in the bathroom so that the ventilation is automatically switched on or off, thus maintaining ideal room humidity values.


Central exhaust air system for indoor bathrooms: For indoor bathrooms, it is recommended to install a central exhaust air system. This is connected to an unoccupied pipe connection or a ventilation shaft through which the air is dehumidified.

With a central exhaust air system, it is important to ensure that fresh air can enter your bathroom from the outside, for example through slits in your bathroom door.

  • Function: A built-in fan extracts the air and thus also the humidity. This air is blown outside via a pipe system or the ventilation shaft. The problem with central exhaust air systems is that although exhaust air can be transported out of the bathroom, no fresh air gets back in - so there is no air exchange. This must then take place in another way, e.g. through ventilation slots in the bathroom door.


Keep in mind when buying:

  • A central exhaust air system is inexpensive and requires little construction work, as no special supply air ducts have to be created.
  • There is no possibility for heat recovery and is therefore not ideal for saving energy, like a decentralised ventilation system with heat recovery.


Are there alternatives to a deaerator?

Yes! If you do not have the possibility to install a deaerator in your bathroom, you should still pay attention to the values of temperature and humidity in your bathroom to prevent the formation of excess moisture and resulting mould for the sake of your health and your living spaces.

In addition to installing a ventilator, there are numerous other ways to reduce humidity and thus achieve ideal indoor air humidity.

  • Draught through ventilation: Even if your bathroom does not have a window, you should open the bathroom door and a window in the adjoining room after a shower or bath. Ventilation is important to create a draught in your flat or house, which removes some of the humidity from your bathroom and improves the indoor climate.
  • Dry your bathroom: When you take a hot shower or bath, a lot of water gets into the air in the form of water vapour. A large part of the resulting water vapour settles on your interior furnishings, tiles, mirrors, grout and shower walls because of the temperature differences. This creates water, which seeps down and settles on your joints and corners - creating a lot of moisture, a paradise for mould. However, if you use a squeegee to remove water from the surrounding tiles, which are particularly misted up, immediately after showering or bathing, and dry the joints and corners of your shower or your bath with a cloth, much of the moisture can be removed, preventing it from becoming a place for mould in the first place.

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Use of dehumidifiers

Among room dehumidifiers there are different categories which help you to filter the moisture from the air. Among the different categories, you can choose between electric, chemical and household dehumidifiers.

  • Electric dehumidifiers: Electric dehumidifiers are devices that are connected to a mains supply and can efficiently absorb large amounts of humidity and accumulate it in a water tank. They often have an automatic mode, whereby the device switches on automatically when the humidity levels in your rooms become too high and switches off when an ideal humidity level is reached. Depending on the type, electric room dehumidifiers can be mounted on the wall and are largely maintenance-free and energy-saving.
  • Chemical room dehumidifiers: Chemical room dehumidifiers are special containers that contain granules that draw the moisture out of the necessary area of your home. All the water that is extracted from the environment drips into a container. A chemical dehumidifier must therefore be replaced every 2-3 months, depending on the frequency of showering or bathing. One advantage of chemical room dehumidifiers is that they are noiseless and mobile. They can also be used in the living room, bedroom or kitchen, for example, if a lot of water vapour is produced around the cooker when cooking and cannot be adequately ventilated.
  • Home remedies: Home remedies can also work wonders in lowering humidity. Salt or cat litter are particularly suitable for this purpose. Even people without cats can buy a bag of cat litter to lower the humidity in their rooms. To do this, fill small bowls with salt or cat litter to a maximum height of 4 cm and place them in your bathroom. As soon as the bowls are full of water, you should empty them, clean them and refill them. However, if you notice that the humidity is rising despite the bowls, you should resort to other methods to prevent mould from forming.
  • Use a fan: To get the humid air out of your bathroom as quickly as possible, you can also set up a fan facing the open bathroom door to blow the water vapour out of the bathroom.
  • Heat properly: Make sure that the room temperature of your bathroom is above a value of 18 degrees Celsius, otherwise the water will settle faster in joints and promote the formation of mould, which can even attack your building fabric.
  • DUSCHKRAFT Home: The all-in-one dehumidifier for the bathroom sustainably lowers the humidity and prevents mould for 375,000 showers.