Parquet flooring develops strong cracks, little warmth under the parquet

Hello dear DIY community,

We are having problems with our real wood parquet flooring in the living room. For some time now, cracks between the wooden planks have increasingly appeared, reaching a width of up to 4 mm. I want to fill the cracks with a parquet filler compound, but I fear that this might prevent the wood from expanding. Ultimately, I am unclear why such significant cracks are forming at all; in any case, I do not want to leave it like this. Could it be because the [Einliegerwohnung] is no longer inhabited and the parquet therefore receives less heat from below? Our house is already 40 years old, and no special structural measures have been taken in recent years.

The cracks indicate in my opinion that the parquet wood is too dry; how high is the humidity in the apartment? If the humidity is too low, the wood dries out or shrinks and forms cracks or too wide gaps between the wood pieces. A parquet expert should take a look at it.

Hello,

I am bringing this up because we have also discovered cracks in our parquet in one room.

The note about the humidity in this room is a first clue. Especially in the winter months, it is very dry and that could be the cause.

But we will consult a parquet fitter to find out what the cause might be.

I will then write the result here.

The cause of cracks in oak parquet is air that is too dry in the room. Such cracks of 4 mm are already considerable. Simply ensure better humidity here with a water bowl or something else.

That is clear, the parquet works and shrinks due to the dryness. I also experience this especially during the heating period. But for me, it is minimal and hardly significant.

This has now also occurred in our house. It bothers me and I want these cracks to disappear. This has happened for the first time in winter. I suspect that the humidity is too low during the harsh heating period. We will probably sand the parquet and reseal it. Then always make sure that the humidity is always around 60 to 70%.