Air permeability of thermally modified hemlock wood

Plinska permeabilnost termično modificiranega lesa zahodne čuge


  • Yaohui Liu Department of Wood Science, Faculty of Forestry, University of British Columbia
  • Stavros Avramidis Department of Wood Science, Faculty of Forestry, University of British Columbia



wood, thermal modification, western hemlock, longitudinal air permeability, specific permeability, temperature effect


Western hemlock (Tsuga heterophylla) is a prevalent coastal species in British Columbia (BC). Its wood has a high potential for thermal modification, a process that can affect numerous physical properties, including air permeability. The current study investigates the longitudinal air permeability of hemlock wood modified at three temperature levels, 170 °C, 212 °C, and 230 °C, and a two-hour treatment length. Permeability values obtained using Darcy’s law and the water-falling volume displacement method were positively correlated with treatment temperature up to 212 °C, after which the permeability decreased slightly. ANOVA followed by the Duncan test revealed that thermal treatment at 212 °C and 230 °C significantly increased air permeability, whereas it was insignificant at 170 °C.


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How to Cite

Liu, Y., & Avramidis, S. (2022). Air permeability of thermally modified hemlock wood: Plinska permeabilnost termično modificiranega lesa zahodne čuge. Les/Wood, 71(2), 25–30.