Humidity in the bathroom

Hello everyone,

we have now been living in our own home for half a year. Currently, there is something that worries me a little because I don’t know if it is normal or not.

Since we moved in, we have had a humidity meter in the main bathroom. I regularly check it. If the humidity is > 60%, I open the window sometimes (as far as I am at home) to reduce this moisture. During the winter months, I lowered the humidity to about 50%. It then stayed there until someone (mostly) showered or bathed. --> afterwards, open the window again and everything was OK.

Currently, however, I notice that despite sometimes keeping the window open for a long time, I can hardly get the humidity below 55% and - what worries me even more - that the humidity rises continuously again after closing the window, even though no moisture (showering or bathing) is added. This morning, the measurement was at 75%.

Partly I can explain it: For example, warm air (in summer) absorbs moisture less well than cold air (in winter). Therefore, possibly the current difficulty in getting the humidity below 55%. But for what reason does the humidity rise continuously again with the window closed, although it remained constantly low during the winter months? The only idea I have: At the current temperatures, the walls are warmer than in winter, which causes more “residual moisture” to dissolve and enter the room.

PS: Actually, there is a ventilator in the bathroom that switches on at high humidity. However, it has not worked properly from the beginning (and the electrician cannot find the fault - the control has already been replaced 3 times). Therefore, still mainly window ventilation.

How many degrees do you have in the bathroom? So does it stay cold after airing out the shower, or does the temperature settle back to a higher level?

How many degrees do you have in the bathroom? So does it stay cold after airing out post-shower, or does the temperature settle back to a higher level?

Since it is the bathroom that the children also use, the underfloor heating temperature remains set the same - i.e., 21-22 degrees). So the temperature after airing out returns to the initial value (easy to notice if you currently have the windows open in the evening/night during cool evening air after bathing/showering - some time after closing the windows, the bathroom is comfortably warm again).

But for what reason does the humidity increase continuously again with closed windows, even though it remained constantly at a low level during the winter months? The only idea I have: With the current temperatures, the walls are warmer than in winter, which causes more "residual moisture" to be released and enter the room.

Hello,

have you tried placing the humidity meter in other rooms in the house for fun to test how the humidity behaves there?

That way you could at least narrow down whether it is "only" a problem in the bathroom, or a problem in the entire building?

Regards,

Dirk

Have you ever put the moisture meter in other rooms in the house just for fun to test how the humidity behaves there?

That way, you could at least narrow down whether it is "just" a problem in the bathroom or a problem in the entire building?

I have already had that thought ;).
We have a second moisture meter in the living room – it continues to run at around 50%.
But just to be safe, I asked my wife yesterday to buy a 3-pack at the hardware store. I will then place these in the bedroom, hallway, and utility room.
In my opinion, the other floor is unproblematic, since the living room, as mentioned, shows nothing else, and in the shower bathroom the exhaust fan works with a timer and humidity sensor.

Then I am curious to see what comes out of it.

Do you have a special cleaner or a particular wallpaper in the bathroom that can regulate moisture?