ᐅ Parquet flooring develops significant cracks and provides little thermal insulation underneath.

Hello DIY community,

We are having issues with our solid wood parquet flooring in the living room. For some time now, cracks have been appearing between the wooden planks, reaching widths of up to 4 mm (0.16 inches).
I want to fill the cracks with a parquet filler, but I’m concerned that this might prevent the wood from expanding. Ultimately, I don’t understand why such large cracks are forming in the first place, and I definitely don’t want to leave it like this. Could it be because the basement flat is no longer occupied, so the parquet is getting less heat from below? Our house is already 40 years old, and no special structural measures have been carried out in recent years.

In my opinion, the cracks indicate that the parquet wood is too dry; what is the humidity level in the apartment? If the humidity is too low, the wood dries out or shrinks, causing cracks or gaps that are too wide between the boards. A parquet flooring specialist should take a look at this.

Hello,

I’m bringing this up because we have also noticed cracks in the parquet flooring in one of our rooms.

The note about the humidity in this room is a good starting point. It is especially dry during the winter months, which could be the cause.

However, we will consult a flooring specialist to determine the exact cause.

I will share the results here.

The cause of cracks in oak parquet flooring is air that is too dry inside the room. Cracks of 4 mm (0.16 inches) are already quite significant. In this case, simply use a bowl of water or another method to improve the humidity level.

That is clear, the parquet does expand and contract, and due to the dryness it shrinks. I experience this especially during the heating season. However, for me, it is minimal and barely noticeable.

This has now appeared in our house as well. It bothers me, and I want these cracks to disappear. This occurred for the first time during the winter. I suspect that the humidity is too low during the intense heating period. We will probably sand and reseal the parquet flooring. Then we will always make sure that the humidity stays around 60 to 70%.