Changes in environment humidity may cause the parquet to expand and contract, resulting in joint openings.
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Joint Opening and Crazing

Changes in environment humidity may cause the parquet to expand and contract, resulting in joint openings. If the environment is excessively dry, with a humidity level below 30%, it is recommendable to use a room humidifier to avoid the openings. An easy trick that may be useful to take the humidity level up is to leave the door open when taking a shower, so that the steam from the shower expands across the house. However, to prevent the problem, it is important to regularly nurture the floor with Alex NutriPlus, which has Lanolin, a natural ingredient that over time hydrates the wood and restores the properties it loses with the use.

Recommended products: ALEX Extra Care Cleaner for Wood, ALEX Extra Care Cleaner for Laminates.