Hardwood and laminate facts: cupping, springing, bowing and twisting and more...

Its all about the Wood Fibres.

Wood is a typical "anisotropic" material. In simple terms, this means that it has no homogeneous structure and moves in various directions. Since the wood has a parallel fibre structure, its mechanical movements depend on the direction of the fibres. Only a deep knowledge of these aspects allows a technologically rational use of wood. The same material can experience different movements depending on the direction of the fibres.

Cupping, Springing, Bowing and Twisting.

Wood, when desiccating, loses all the available water (lymph) located in the cell cavities. This happens without causing any deformation. After this first phase, water within the cell walls will dry. As a consequence, the weight of these cell walls will drop and this leads to the characteristic phenomenon of shrinking. On a macroscopic level, this behavior creates changes in form and dimensions: the so called "movements of the wood".

Wood loses and acquires moisture.

Wood is a living material, sensitive to the constant changes within its surroundings. It suffers in particular ways to variations in the humidity of the air and adapts itself accordingly to a certain extent. If a piece of wood is placed in a very humid room, it will tend to absorb a part of that humidity. If, however, the same piece of wood is placed in a dry environment, the wood will react in the opposite way, abandoning part of the appropriate humidity.

Stability and movement.

Since wood constantly strives to reach its' equilibrium with the environment, it will inevitably make very slow but very real movements that will change its form and dimensions. It is clear that this "behaviour" can create problems when wood is used for the construction of a floor because apart from experiencing normal strong climatic influences, it may even be subjected to water spillages. Luckily, technology has found the solution to this problem: today wood and stability finally work well together.

The ambient climate.

Man has a more immediate perception of temperature than of humidity. Humidity control inside a building is often neglected, resulting in critical conditions for a wooden floor. In wintertime, the continuous occurrence of heating systems creates very dry atmospheric conditions, which can lead the wood to shrink. In summertime, vice versa, a higher environmental moisture creates more humid conditions which can cause the wood to swell.

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