Comparison between Predicted and Measured Moisture Content and Climate in 12 Monitored Timber Structures in Switzerland

Abstract

Wood is a hygroscopic material that primarily adapts its moisture content to the surrounding relative humidity. The climate in a structure or building depends on the building type and the region the structure is located in. In this study, the effect of region on the moisture content of wood was investigated. Measurements taken in 12 ventilated timber structures were compared to the theoretical equilibrium moisture content calculated from the relative humidity and temperature in 107 meteorological stations across Switzerland. The monitored load-bearing elements were made of softwood and protected from the direct impact of weather. The climatic conditions around the Alps, a mountain range that runs from France to Austria and crosses Switzerland, can be divided into the following three different regions: (1) south of the Alps, where the climate is affected mainly by the Mediterranean sea; (2) north of the Alps, where the climate is affected by the Atlantic Ocean; and (3) the inner Alps, where the climate is considered to be relatively dry. The climatic conditions of the three separate regions were reflected in the measurements made in the monitored timber structures. Differences between the regions were quantified. The moisture content and relative humidity, similarly to temperature, depended on altitude (above sea level).

Damage Assessment of Pine Wood Facades in the First Years of Service for Sustainable Maintenance

“…For instance, the moisture content of wood elements may influence the results of ultrasonic waves, sclerometric, and resistance tests [22,25,26]. This could be especially crucial in areas with climate changes with moisture increase [27,28] and in areas with harsh conditions, such as near the sea where the moisture level is extremely high.…”