FAQ: Why does natural wooden flooring parquet expand and shrink?

All materials are elastic due to the weather changing. Natural wood is the same. Each kind of wood will have a different elasticity ratio.

Technically, the difference between moisture of wooden flooring and humidity of environment makes the expansion and contraction. When the humidity in the environment higher, water in wooden flooring will escape to the environment. Then, the wooden flooring shrinks. In the opposite, when the humidity in the environment is lower than the humidity of wooden flooring, environmental water penetrates into the wooden flooring. This water is called free water. This makes the wooden flooring expansion.


Normally, the width of wooden flooring parquets stretch. The length of parquets do not stretch very much. That is why when installing wooden flooring, construction units usually install along the length of the room. Thus, the total expansion of the wooden flooring will be the lowest.


The rate of expansion of the wooden floor in the environment of Vietnam as follows:

  • Solid wooden flooring (0.5% – 2%).
  • Engineered Wood Flooring: (0.1% – 0.2%).

In manufacturing, Polytech uses high technology to ensure that the moisture of the wooden floor parquets balance with the environmental humidity using wooden floor. The level of moisture balance compared to environmental slab is 12% (+/-2). If the humidity is lower than the moisture of the parquets, the company must decrease the moisture of the floor parquets. Thus, the water in the environment will absorb into the wooden flooring and create the expansion.


Moisture of natural wooden flooring is different for different user markets. For example, in Ho Chi Minh City, the moisture of floor should be about 10% to 14%, Hanoi and the northern provinces are 12% to 16%, in export markets such as Japan, Europe, Eastern Europe, Middle East, Canada, America … could be different due to different natural environment.

Before exporting, Polytech do a lot of research of that export market. The research covers the environment, humidity, … to ensure the product when the products reach consumers, consumers can use long-term.

To measure the moisture of the wooden flooring and the natural environment, you may need a dedicated device. Please contact our company for more advice. We are very happy to provide more information before you make decisions for your home.