In contact with indoor air, wood materials have a high potential to passively reduce the indoor humidity fluctuations resulting from internal moisture loads and outdoor humidity fluctuations. This ability, characterized by the so-called moisture buffering capacity of building materials, has attracted increasing attention within building physics but the development of suitable method to appraise and quantify this phenomenon is still under discussion. Here, a comprehensive account is given of spatially resolved moisture absorption (desorption) into (from) Scots pine by proton magnetic resonance imaging (1H MRI) when one surface is exposed to stepped cycles of humidity. The bound-water distribution in Scots pine with a spatial resolution on a sub-millimetre scale was acquired when one of the orthotropic directions of the wood material was exposed to typical indoor day-to-day moisture fluctuations. The moisture distribution of coated Scots pine was also imaged. The nuclear magnetic resonance imaging measurements clearly show a potential to provide accurate spatial information about the wood-water interaction below the fibre saturation point and hence to characterize the moisture buffering capacity of wood materials.
Keywords: Bound water,Proton magnetic resonance imaging (1H MRI),Moisture buffering capacity
Authors
Stéphane Hameury
KTH – Dept. of Civil and Architectural Engineering, Stockholm, Sweden
Login to download the PDF