Moisture redistribution in full-scale wood-frame wall assemblies: measurements and engineering approximation

Charles R. Boardman; Samuel V. Glass; Samuel L. Zelinka

doi:10.3390/buildings10080141

Treesearch

Moisture redistribution in full-scale wood-frame wall assemblies: measurements and engineering approximation

Formally Refereed

Authors:

Charles R. Boardman, Samuel V. Glass, Samuel L. Zelinka

Year:

2020

Type:

Scientific Journal

Station:

Forest Products Laboratory

DOI:

https://doi.org/10.3390/buildings10080141

Source:

Buildings. 10(8): 141. 25 p.

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Download (PDF 3.17 MB): https://research.fs.usda.gov/download/treesearch/60971.pdf

Abstract

A counter-balanced mass measurement system was constructed to allow measurement of water loss from a full-scale wood-framed wall assembly. Water was injected onto a localized area of paper towel adjacent to the oriented strand board (OSB) wall sheathing. Moisture pins in the OSB and relative humidity/temperature sensors inside the insulated wall cavity monitored conditions as the wall dried out. The wetted OSB area’s moisture content dropped at a faster rate than the total mass of the wall, indicating moisture redistribution within the wall. A simple model was used to calculate overall moisture redistribution, which was characterized using a near-exponential decay function. This simplifcation of the inherently three-dimensional physics of moisture redistribution could be incorporated into the one-dimensional hygrothermal models often used in research and engineering practice.

Keywords

Moisture performance, moisture redistribution, drying potential, building envelope, oriented strand board, mass balance

Citation

Boardman, Charles R.; Glass, Samuel V.; Zelinka, Samuel L. 2020. Moisture redistribution in full-scale wood-frame wall assemblies: measurements and engineering approximation. Buildings. 10(8): 141. 25 p.