Home » Functional Material » Building Material » WOOD AS A BUILDING MATERIAL


WOOD AS A BUILDING MATERIALWood is a building material used for a long time, the proof none other than Jesus (in the year 0) exercised the profession of carpenter. However, the arrival of new building materials such as steel and concrete at the turn of the twentieth century, have lost the pedestal to this natural and living material. Nowadays, the fashion of the wood comes back. It is only necessary to know how to work it, an expertise held by professional cabinetmakers of all types.

How can the wood material change according to its environment?

This natural material has the ability to absorb moisture, so the moisture content causes changes in shrinkage and swelling of the wood. Added to other environmental conditions, moisture is responsible for wood rot. Hygroscopicity or moisture content is the ratio of the mass of water present in the wood to the dry wood mass expressed as a percentage.

Wood contains water in two forms. On the one hand, water is absorbed inside the cell walls when it is in moisture, and on the other hand, the free water inside the cell cavities will evaporate first when dry wood, until the moisture content corresponding to the saturation point of the fibers is reached, approximately 30% for most wood species. Beyond this moisture content, no more swelling occurs.

Below the saturation point of the fibers, the wood loses or absorbs moisture until the moisture content is in equilibrium with that of the ambient air. It is important to remove the water contained in the wood elements before use so that the shrinkage does not occur again after installation. Water can be removed by drying, naturally or by drying. In North America, the latter is between 8 and 12%. The National Building Code requires that the moisture content of the wood elements of the structure does not exceed 19% at the time of their implementation.

Wooden Covered Bridge_Building_Submission Renovation

Needless to say, the wood burns, which can make it seem like a log cabin is more vulnerable to fire than a contemporary concrete construction. Nevertheless, if it is less than 37 degrees Celsius, temperature changes have very little influence on the resistance of the wood . Wood is an excellent thermal insulator because of its cellular structure containing a large amount of cavities. Wood withstands 500 times more heat than steel and 7 times more than concrete, in addition to storing 3 times more heat than concrete.

Even if the wood burns, its slow combustion generates on the surface of the wood a carbon layer isolating the unburned wood from the heat released by the flames, a phenomenon which reduces the rate of carbonization. The non-burned part only loses 10% to 15% of its total resistance. In case of fire, if firefighters arrive on time, the wooden elements of your house can be saved.

The hygroscopicity of the wood can change the density of the material, ie the weight and the volume. Density is measured as the difference between the weight of the wood in the green or basal state and the weight of the completely dry wood through the volume of water.

Leave a Reply

Your email address will not be published. Required fields are marked *