Current Research

Wood structures can endure for centuries if they remain sufficiently dry. Many of the challenges of using wood as a structural material (such as mold growth, wood decay, corrosion of fasteners, and dimensional instability) arise from excessive moisture levels or large changes in moisture content.

Dr. Glass leads the Building Moisture and Durability Team within the Building and Fire Sciences Research Work Unit at the Forest Products Laboratory. His research focuses on the relationships between moisture, energy-efficiency, and durability in residential and non-residential wood-based buildings. Primary research objectives include

Research Interests

• Durability of energy-efficient buildings
• Building envelope performance
• Moisture management in buildings
• Heat, air, and moisture transfer
• Wood-moisture relations
• Hygrothermal properties of wood products
• Interior and exterior moisture loads
• Instrumentation for monitoring moisture levels in building assemblies

Past Research

Dr. Glass conducted his doctoral research in the Department of Chemistry at the University of Wisconsin-Madison. He investigated how surfactant films at the gas-liquid interface control gas uptake and evaporation of water. These studies contributed to understanding chemical reactions that occur in sulfuric acid droplets in the upper troposphere and lower stratosphere, which affect ozone levels.

Why This Research is Important

The sustainability and health of America's forests depend on sound conservation practices, including utilization. Efficient use of wood as a green building material is important for climate change mitigation because wood products store carbon for as long as the building exists. The longer the service life, the greater the benefit. Wood products require much less energy to process than other building materials such as steel or concrete, and use of wood produces less air pollution, solid wastes, and greenhouse gases. Efficient wood utilization also reduces the risk and impacts of wildfire, provides incentives for private landowners to maintain forest land, and provides a critical source of jobs in rural America. These benefits hinge on efficient and proper use of wood in construction, and moisture control is essential because of wood's vulnerability to moisture problems. Moisture management is also critical because excessive dampness in buildings has been linked to negative health effects.

Education

• University of Wisconsin-Madison, Ph.D. Physical Chemistry 2005
• Calvin College, Grand Rapids, MI, B.A. Chemistry/Classical Civilization/Archaeology 1998

Professional Experience

Professional Organizations

• Society of Wood Science and Technology (SWST), Member (2008 - Current)
• American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), Member (2005 - Current)
  Research Subcommittee Chair and Voting Member, Technical Committee (TC) 4.4, Building Materials and Building Envelope Performance. Secretary, Vice Chair, and Voting Member, Standing Standard Project Committee (SSPC) 160, Criteria for Moisture-Control Design Analysis in Buildings. Voting Member, TC 1.12, Moisture Management in Buildings.

Featured Publications & Products

• Glass, Samuel V; Boardman, Charles R.; Thybring, Emil Engelund; Zelinka, Samuel L. 2018. Quantifying and reducing errors in equilibrium moisture content measurements with dynamic vapor sorption (DVS) experiments.
• Glass, Samuel V.; Gatland II, Stanley D.; Ueno, Kohta; Schumacher, Christopher J. 2017. Analysis of improved criteria for mold growth in ASHRAE standard 160 by comparison with field observations.
• Glass, Samuel V.; Zelinka, Samuel L. 2010. Moisture relations and physical properties of wood.
• Glass, Samuel V.; Wang, Jieying; Easley, Steve; Finch, Graham. 2013. Chapter 10: Enclosure--Building enclosure design for cross-laminated timber construction.
• Glass, Samuel; Kochkin, Vladimir; Drumheller, S.; Barta, Lance. 2015. Moisture Performance of Energy-Efficient and Conventional Wood-Frame Wall Assemblies in a Mixed-Humid Climate.
• Glass, Samuel V.; TenWolde, Anton; Zelinka, Samuel L. 2013. Hygrothermal Simulation: A Tool for Building Envelope Design Analysis.
• Zelinka, Samuel L.; Derome, Dominique; Glass, Samuel V. 2011. Combining hygrothermal and corrosion models to predict corrosion of metal fasteners embedded in wood.
• TenWolde, Anton; Glass, Samuel V. 2013. Moisture in Crawl Spaces.
• Zelinka, Samuel L.; Bourne, Keith J.; Hermanson, John C.; Glass, Samuel V.; Costa, Adriana; Wiedenhoeft, Alex C. 2015. Force-displacement measurements of earlywood bordered pits using a mesomechanical tester.

Publications

• Zelinka, Samuel L.; Kirker, Grant T.; Bishell, Amy B.; Glass, Samuel V. 2020. Effects of wood moisture content and the level of acetylation on brown rot decay.
• Zelinka, Samuel L.; Glass, Samuel V; Thybring, Emil Engelund. 2020. Evaluation of previous measurements of water vapor sorption in wood at multiple temperatures.
• Kordziel, Steven ; Glass, Samuel V; Boardman, Charles R.; Munson, Robert A.; Zelinka, Samuel L.; Pei, Shiling ; Tabares-Velasco, Paulo Cesar. 2020. Hygrothermal characterization and modeling of cross-laminated timber in the building envelope.
• Boardman, Charles R.; Glass, Samuel V; Zelinka, Samuel L. 2020. Moisture redistribution in full-scale wood-frame wall assemblies: measurements and engineering approximation.
• Lepage, Robert ; Glass, Samuel V; Knowles, Warren ; Mukhopadhyaya, Phalguni . 2019. Biodeterioration models for building materials: critical review.
• Boardman, C.R. ; Glass, Samuel V; Munson, Robert ; Yeh, Borjen ; Chow, Kingston . 2019. Field moisture performance of wood-framed walls with exterior insulation in a cold climate.
• Boardman, Charles R.; Chow, Kingston ; Glass, Samuel V; Yeh, Borjen . 2019. Hygrothermal modeling of wall drying after water injection.
• Thybring, Emil Engelund; Glass, Samuel V; Zelinka, Samuel L. 2019. Kinetics of water vapor sorption in wood cell walls: state of the art and research needs.
• Kordziel, Steven ; Pei, Shiling ; Glass, Samuel V; Zelinka, Samuel ; Tabares-Velasco, Paulo Cesar. 2019. Structure moisture monitoring of an 8-story mass timber building in the Pacific Northwest.
• Thybring, Emil E.; Boardman, Charles R.; Glass, Samuel V; Zelinka, Samuel L. 2019. The parallel exponential kinetics model is unfit to characterize moisture sorption kinetics in cellulosic materials.
• Zelinka, Samuel L.; Bourne, Keith J.; Glass, Samuel V; Boardman, Charles R.; Lorenz, Linda ; Thybring, Emil Engelund. 2018. Apparatus for gravimetric measurement of moisture sorption isotherms for 1-100 g samples in parallel.
• Pásztory, Zoltán ; Horváth, Tibor ; Glass, Samuel V; Zelinka, Samuel . 2018. Experimental investigation of the influence of temperature on thermal conductivity of multilayer reflective thermal insulation.
• Kordziel, Steven ; Glass, Samuel V; Pei, Shiling ; Zelinka, Samuel L.; Tabares-Velasco, Paulo Cesar. 2018. Moisture monitoring and modeling of mass-timber building systems.
• Glass, Samuel V; Boardman, C.R. ; Yeh, Borjen ; Chow, Kingston . 2018. Moisture monitoring of wood-frame walls with and without exterior insulation in the Midwestern U.S.
• Zelinka, S.L. ; Kordziel, S. ; Pei, S. ; Glass, S.V. ; Tabares-Velasco, P.C. . 2018. Moisture monitoring throughout the construction and occupancy of mass timber builidings.
• Zelinka, Samuel L.; Glass, Samuel V; Thybring, Emil Engelund. 2018. Myth versus reality: do parabolic sorption isotherm models reflect actual wood water thermodynamics.
• Passarini, Leandro ; Zelinka, Samuel L.; Glass, Samuel V; Hunt, Christopher G. 2017. Effect of weight percent gain and experimental method on fiber saturation point of acetylated wood determined by differential scanning calorimetry.
• Glass, Samuel V.; Boardman, Charles R.; Zelinka, Samuel L. 2017. Short hold times in dynamic vapor sorption measurements mischaracterize the equilibrium moisture content of wood.
• Boardman, Charles; Glass, Samuel V.; Lebow, Patricia K. 2017. Simple and accurate temperature correction for moisture pin calibrations in oriented strand board.
• Zelinka, Samuel L.; Glass, Samuel V.; Jakes, Joseph E.; Stone, Donald S. 2016. A solution thermodynamics definition of the fiber saturation point and the derivation of a wood-water phase (state) diagram.
• Zelinka, Samuel L.; Passarini, Leandro; Colon Quintana, José L.; Glass, Samuel V.; Jakes, Joseph E.; Wiedenhoeft, Alex C. 2016. Cell wall domain and moisture content influence southern pine electrical conductivity.
• Zelinka, Samuel L.; Glass, Samuel V.; Boardman, Charles R.; Derome, Dominique. 2016. Comparison of the corrosion of fasteners embedded in wood measured in outdoor exposure with the predictions from a combined hygrothermal-corrosion model.
• Glass, Samuel V.; Yeh, Borjen; Herzog, Benjamin J. 2016. Effects of Exterior Insulation on Moisture Performance of Wood-Frame Walls in the Pacific Northwest: Measurements and Hygrothermal Modeling.
• Zelinka, Samuel L.; Glass, Samuel V.; Boardman, Charles R. 2016. Improvements to water vapor transmission and capillary absorption measurements in porous materials.
• Zelinka, Samuel L.; Glass, Samuel V.; Boardman, Charles R.; Derome, Dominique. 2016. Moisture storage and transport properties of preservative treated and untreated southern pine wood.
• Zelinka, Samuel L.; Wiedenhoeft, Alex C.; Glass, Samuel V.; Ruffinatto, Flavio. 2015. Anatomically informed mesoscale electrical impedance spectroscopy in southern pine and the electric field distribution for pin-type electric moisture metres.
• Boardman, C.R.; Glass, Samuel V. 2015. Basement radon entry and stack driven moisture infiltration reduced by active soil depressurization.
• Boardman, CR; Glass, Samuel V. 2015. Moisture transfer through the membrane of a cross-flow energy recovery ventilator: Measurement and simple data-driven modeling.
• Zelinka, Samuel L.; Quintana, José L. Colon; Glass, Samuel V.; Jakes, Joseph E.; Wiedenhoeft, Alex C. 2015. Subcellular Electrical Measurements as a Function of Wood Moisture Content.
• Pásztory, Zoltán; Horváth, Tibor; Glass, Samuel V.; Zelinka, Samuel L. 2015. Thermal Insulation System Made of Wood and Paper for Use in Residential Construction.
• Glass, Samuel V.; Zelinka, Samuel L.; Johnson, Jay A. 2014. Investigation of Historic Equilibrium Moisture Content Data from the Forest Products Laboratory.
• Zelinka, Samuel L.; Glass, Samuel V.; Derome, Dominique. 2014. The effect of moisture content on the corrosion of fasteners embedded in wood subjected to alkaline copper quaternary treatment.
• Glass, Samuel V. 2013. Hygrothermal Anaylsis of Wood-Frame Wall Assemblies in a Mixed-Humid Climate.
• Boardman, C.R.; Glass, Samuel V. 2013. Investigating Wind-Driven Rain Intrusion in Walls with the CARWASh.
• Jakes, Joseph E.; Plaza, Nayomi; Stone, Donald S.; Hunt, Christopher G.; Glass, Samuel V.; Zelinka, Samuel L. 2013. Mechanism of Transport Through Wood Cell Wall Polymers.
• Clausen, Carol A.; Glass, Samuel V. 2012. Build Green: Wood Can Last for Centuries.
• Zelinka, Samuel L.; Lambrecht, Michael J.; Glass, Samuel V.; Wiedenhoeft, Alex C.; Yelle, Daniel J. 2012. Examination of water phase transitions in Loblolly pine and cell wall components by differential scanning calorimetry.
• Boardman, C.R.; Glass, Samuel V.; Carll, Charles G. 2011. Moisture meter calibrations for untreated and ACQ-treated southern yellow pine lumber and plywood.
• Glass, Samuel V. 2010. A laboratory facility for research on wind-driven rain intrusion in building envelope assemblies.
• Boardman, C. R.; Glass, Samuel V.; Carll, Charles G. 2010. Estimating foundation water vapor release using a simple moisture balance and AIM-2 : case study of a contemporary wood-frame house.
• Zelinka, Samuel L.; Derome, Dominique; Glass, Samuel V. 2010. From laboratory corrosion tests to a corrosion lifetime for wood fasteners : progress and challenges.
• Glass, Samuel V.; Carll, Charles G.; Curole, Jay P.; Voitier, Matthew D. 2010. Moisture performance of insulated, raised, wood-frame floors : a study of twelve houses in southern Louisiana.
• Zelinka, Samuel L; Glass, Samuel V. 2010. Water vapor sorption isotherms for southern pine treated with several waterborne preservatives.
• Glass, Samuel V.; TenWolde, Antoni. 2009. Review of moisture balance models for residential indoor humidity.
• Glass, Samuel V.; Carll, Charles G. 2009. Moisture meter calibration for untreated and ACQ-treated southern yellow pine plywood.
• Clausen, Carol A.; Glaeser, Jessie A.; Glass, Samuel V.; Carll, Charles. 2009. Occurrence of mold in a two-story wood-frame house operated at design indoor humidity levels.
• Zelinka, Samuel L.; Glass, Samuel V.; Stone, Donald S. 2008. A percolation model for electrical conduction in wood with implications for wood-water relations.
• Glass, Samuel V. 2007. Measurements of moisture transport in wood-based materials under isothermal and nonisothermal conditions.
• Glass, Samuel V.; TenWolde, Anton. 2007. Review of in-service moisture and temperature conditions in wood-frame buildings.

Research Highlights

Highlight	Title	Year
FPL-2010-005	A percolation model for water and electrical conduction in wood with implications for durability Recently, researchers at the Forest Products Laboratory and University of Wisconsin have developed a new model of electrical conduction in wood ...	2010
FPL-2010-001	Centennial Edition, Wood Handbook—Wood as an Engineering Material The Wood Handbook—Wood as an Engineering Material serves as a primary reference document for a wide variety of users-from the general publ ...	2010
FPL-2019-71	Development of New Kinetics Models for Water Vapor Sorption in Wood Wood is constantly exchanging water with its environment and these exchanges control nearly all of wood's amazing properties. USDA Forest Servic ...	2019
FPL-2017-120	Improving experimental techniques that probe wood-moisture interactions Prior methods using dynamic vapor sorption instruments mischaracterized the equilibrium moisture content of wood. Equilibrium is reached after m ...	2017
FPL-2018-23	Improving the Accuracy of Automated Instruments for Moisture in Wood Automated instruments are increasingly used for measuring the equilibrium moisture content of wood. Research finds that common methods have much ...	2018
FPL-2019-76	Keeping Wood-Frame Housing Safe and Warm Is it okay to add exterior insulation and cover the wood sheathing to make your home even more energy-efficient? USDA Forest Service researchers ...	2019
FPL-2015-199	Managing Moisture in Energy-efficient Wall Systems Moisture durability is critical for design and construction of energy-efficient buildings. Field measurements of moisture characteristics for hi ...	2015
FPL-2010-004	Modeling indoor humidity in homes Indoor humidity levels in a home influence not only occupant comfort and indoor air quality but also the durability of the building, especially ...	2010
FPL-2011-11	Moisture Control in Crawl Spaces in Louisiana Builders and homeowners in the Gulf Region often ask how to insulate a crawl space to avoid moisture problems. The Forest Products Laboratory (F ...	2011
FPL-2019-80	Monitoring Moisture Levels in Mass Timber Buildings Detailed measurements on moisture levels in mass timber buildings in the United States are scarce. USDA Forest Service researchers are working w ...	2019
FPL-2014-175	Possibilities and Pitfalls of Computer Simulation for Building Moisture Analysis Moisture problems are much less expensive to correct in the building design phase than after the building is constructed. Computer-based simulat ...	2014
FPL-2017-114	Scientists study how water changes wood Water causes a host of wood damage mechanisms such as mold, decay, fastener corrosion, and splitting. This research elucidates how water chan ...	2017
FPL-2018-22	Updating a Building Design Standard with Improved Criteria for Preventing Mold Growth A consensus standard for building design that addresses moisture control analysis was recently revised to improve the criteria for preventing mo ...	2018
FPL-2013-143	Wood Construction Goes Beyond Its Traditional Roots As interest in sustainable building options continues to grow. Wood construction is going beyond its traditional roots in housing and expanding ...	2013