Methods to determine wood moisture content and their applicability in monitoring concepts.

The reaction of wood to moisture forms an
integral part of any task in connection with this natural and
renewable building material. Changes in wood moisture
content lead to changes of virtually all physical and
mechanical properties (e.g. strength and stiffness properties)
of wood. Another effect of changes of the wood
moisture content is the associated shrinkage or swelling of
the material. The existence of high moisture content can
initiate decay or growth of fungi. The correct estimation of
timber moisture content and the subsequent initiation of
potentially necessary measures are therefore essential tasks
during the planning, execution and maintenance of buildings
built with wood or wood-based products. This is
supported by the high amount of damages on structural
timber elements that can be attributed to ignorance of the
reaction of wood to moisture. Also supported by this fact,
the in situ monitoring of moisture content of structural
timber elements has recently received considerable interest
and growth. This paper describes common methods to
determine wood moisture content and evaluates them with
respect to their applicability for monitoring concepts.
Keywords Wood Moisture Measurement Monitoring Temperature Relative humidity Moisture
gradients Shrinkage Swelling