Anyone who has the floors of their living space lined with parquet in summer can get a nasty surprise in winter: The wood deforms upwards or downwards along the middle due to permanently high room temperatures of 25 degrees Celsius and more with low relative humidity of less than 40 percent at the same time. In such a case, the parquet installer is not to blame. The Regional Court of Saarbrücken considers the occupant to be obliged to point out his heating behaviour to the expert, because this is to be considered an extraordinary circumstance (judgement of 14 December 2010, file number 15 O 200/10).
Wood lives and is valued not least for its positive influence on the indoor climate. Its hygroscopic ability to absorb water from the air and release it again as required can be seen in the raw material when you look closely. The smallest gaps are created by the release of water, which close again as the humidity in the room increases due to the swelling of the wood. However, if the temperature and dryness permanently exceed a limit, the parquet will be irreparably damaged. This usually happens in the cold season, when the relative humidity during the heating period is significantly lower than in the other months.
This was also the case in the matter underlying the judgement of the Saarbrücken Regional Court. The excessive heating behaviour in combination with dry room air led to the permanent deformation of the parquet. Although the parquet installer had only handed over a care brochure with corresponding explanations on room temperatures and humidity after completing his work, in the judges' opinion it was not too late to take appropriate measures such as an air humidification system. The client had to pay the bill in full.
«A balanced room climate is of great importance for the longevity of a parquet floor. If a parquet floor is exposed to a low humidity of less than 30% for too long, the wood may deform or cracks may appear. For this reason, a humidity of between 35% - 70% is recommended by the parquet layer.»
In winter, indoor humidity in living and working spaces often falls to dramatically low levels: 20 percent relative humidity is not uncommon - far from the ideal range of 40 to 60 percent. In everyday life, air humidity is supplied by people and moisture-producing activities such as showering and cooking, or with the fresh air. In winter, when the heated room air could absorb more humidity than is present, this is usually not enough. The result: the relative humidity drops steadily and the parquet begins to deform as soon as the hygroscopic tolerance range of the wood has been exhausted. Furniture, antiques or musical instruments made of wood are also at risk of similar damage, and paintings and books also suffer under these conditions. Furthermore, the dry air also affects people's health, regardless of their age.
Effective and safe protection is provided by additional humidification systems, ideally with automatic control of the air humidity between 40 and 60 percent. The market for humidifiers is huge. However, the variety of products also has its pitfalls. Inferior mobile humidifiers are often not only too inefficient and unreliable, but in the worst case they also cause hygienic problems. For this reason, it is advisable to seek individual advice from a specialist for a suitable lasting and permanently installed solution.
Permanently installed humidification systems can be easily integrated into the existing residential ventilation system or installed as a separate solution in a house or flat. A fixed installation has great advantages over a mobile humidifier:
Incidentally, balanced air humidity not only protects against damage to furnishings, but also protects people: Dry skin, a clogged voice, reddened eyes or dried-out mucous membranes are direct consequences of insufficient room humidity. In addition, there is an increased risk of infection of the respiratory tract. Allergies and asthmatic symptoms can also often be traced back to a lack of humidity.
Everything that is dear to people - from furniture to health - is directly dependent on the water content of the surrounding air. In view of this, it is hardly understandable that air humidity is perceived rather neglectfully as an essential indoor climate factor. If homeowners with parquet floors in their living spaces would take this into account, they would not only be spared parquet damage, at the same time they would also have created a perfect and above all healthy indoor climate.
Sponsored from Condair
Werner Adler
Head of Marketing for Western Europe
Condair AG
