Wooden parquet has always been a model of flooring – it is with which all others are compared.
Natural wood is known as an anisotropic material, which means that its properties are different in different directions. You can observe the manifestation of this fact in the process of wood processing: the direct direction sometimes swells several times more than the transverse direction.
In order to correctly predict the “behavior” of a parquet board after installation, it is necessary to remember the following relationship: if the moisture content of the wood structure changes by 1%, the thickness and width will change by 0.25%, and this is true for materials that have both radial and tangential cuts.
Due to the fact that wood is heterogeneous, the deformation of the boards is mainly determined by the width to thickness ratio.
Experts agree that the following statement is true: the thinner the material, the greater its tendency to swell and warp.
To prevent these negative phenomena, as a rule, they strive to select the specified ratio equal to 4, and for wood that is a priori prone to deformation – 3.5.
In fact, the deformation of boards strongly depends on the time of year, more precisely, on temperature and humidity. At a temperature of 20C, the humidity changes from 30% in winter, with heating on, to 60% in summer, wood doubles its resorption moisture content. As for the specific deformation, for a board with a width of 60 mm, experts offer the following parameters:
- 0.75 mm is the standard for any type of wood, except those listed below;
- 0.78 mm – oak dies;
- 0.48 mm – oak boards with a radial cut;
- 1.08 mm – oak boards with a tangential cut;
- 0.93 mm – beech boards.
