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Studies in Moisture Adsorption and Thickness Swelling: Low and High Humidity
Greg S. McLellan1 and Ralph E. Moon2
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DOI:10.17265/1934-7359/2025.02.001
1. PEGroup Consulting Engineers, Inc., Weston, FL 33326, USA
2. Ralph E. Moon Consulting, LLC, Tampa, FL 33629, USA
Composite wood products (i.e., particleboard, medium density fiberboard, oriented strand board, plywood) used in cabinets, shelving, and base trim express varying degrees of thickness swelling when exposed to a sustained moisture source. Thickness swelling occurs when cellulose fibers adsorb water molecules and swell after attaining a moisture content of 29% to 36%. Observations of thickness swelling were made to refine water loss duration estimates. Thickness swell height is the result of several intrinsic factors (wood species, density, adhesive resin, heat pressing conditions). This study examined an extrinsic factor, humidity, at elevated (>95%RH) and ambient (50%RH) conditions. Specimens subjected to moisture for longer periods (8-10 weeks) experienced gradual darkening from accumulated biomass and fungal deterioration of the wood surfaces. The study revealed that high humidity conditions expressed higher rates of thickness swelling and that estimates of water loss duration should consider the influence of ambient humidity during and following a water release.
Composite wood, duration of loss, moisture exposure, thickness swell.
Journal of Civil Engineering and Architecture 19 (2025) 53-65
doi: 10.17265/1934-7359/2025.02.001
[1] Halligan, A. F. 1970. “A Review of Thickness Swelling in Particleboard.” Wood Science and Technology 4: 301-12.
[2] Martin, F. S. E. n.d. Expansion of Wetted Plywood and OSB Panels. Structure Magazine, pp. 38-9.
[3] Carll, C.G, 1997. “Review of Thickness Swell in Hardboard Siding: Effect of Processing Variables” Gen. Tech Rep. FPL-GTR-96. U.S. Department of Agriculture, Forest Service, Forest Products Laboratory, 10 p.
[4] Baldwin, S. 1988. “Dimensional Stability Problems in Fiber Board Products.” In Wood Science Seminar 1: Stabilization of the Wood Cell Wall: Proceedings of a Seminar, edited by O. Suchsland, December 15-16, 1987. East Lansing, MI: Michigan State University.
[5] Moon, R. 2012. “Interpreting Continuous v. Repeated Water Damage.” In The Sixth Forensic Engineering Congress Proceedings, October 31-November 3, 2012. New York: American Society of Civil Engineers.
[6] Da Dalt, A. 2016. Wood Decay and Strength Loss. Millbrook: Wood Science Consulting.
[7] Davis, B. and R. Moon, 2015. Thickness Swell in Particle Board: A Forensic Tool for Duration of Loss, American Society of Civil Engineering, The Seventh Forensic Engineering Congress Proceedings, November 15-18, 2015. New York: American Society of Civil Engineers.