Wood moisture

What is wooden moisture?

Wood owns a cell structure, with cell walls and hollow cavities. In the living tree cell walls and hollow cavities are filled at most with water (cell juice). If the tree is liked and dries the wood, the hollow cavities of the cells and only empty first afterwards the dampness decreases in the cell walls. Vice versa if wood becomes wet the cell walls up to the saturation take up first the dampness and only afterwards the water gathers in the cell hollow cavities. However, this happens only in special cases, e.g., with water storage.

The point with which during the drying the cell hollow cavities are empty and the water from the cell walls starts to decrease, is the fiber saturation point. Or differently expressed, the point from him the cell walls are fed.

Wooden dampness - definition

The wooden dampness (short sign: and, unity: %) is defined as a proportional relation of the mass of the water in the wood to the mass of the completely dry wood (dry weight). Practically a piece of wood is weighed, afterwards dried completely and weighed again. The weight difference in percent of the dry weight of the wood is the wooden dampness which had the concerning piece of wood. The arithmetic way moreover is: ((Wet weight / dry weight)-1) *100%. Accepted, a piece of wood weighs 125 g and after the drying 100 g before the drying, then the wood ((125/100) had-1) *100% = 25%.

This kind of the wooden dampness regulation is called "Darrprobe", the entire dry of the wood will kiln-dry as called and the weight of the completely dry wood is the dry weight.

Wooden dampness measurement with the opposition method

The wooden dampness is derived from the Ohmschen opposition which decreases with rising wooden dampness. In addition the electrodes about which the electric opposition of the wood is measured are introduced in the wood.