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In-Situ Measurement of the Moisture Content of Building Materials Using Ultra-Wideband Radio Waves.


pdf icon In-Situ Measurement of the Moisture Content of Building Materials Using Ultra-Wideband Radio Waves. (162 K)
Healy, W. M.

NRCC-46103;

Research in Building Physics and Building Engineering. Building Physics Conference, 3rd International. Proceedings. August 27-31, 2006, Montreal, Canada, Taylor and Francis/Balkema, Leiden, Netherlands, Editor(s), 173-180 pp, 2006.

Keywords:

building materials; moisture content; radio waves; transmission; tests; strand board; plywood; gypsum board; wood; data analysis; sensitivity; experiments

Abstract:

A study was carried out to determine the feasibility of commercial, off-the-shelf, and potentially low-cost ultra-wideband radio hardware to serve as a measurement tool for the moisture content of building materials. The study examined both reflections from and transmission through an envelope assembly when pulses with a center frequency of 4.7 GHz were emitted towards the materials. The reflected energy was found to be the best measure of moisture content. Tests on oriented strand board, plywood, and gypsum board showed that a linear trend was found between the reflected energy and moisture content of the two wood products, but the range of moisture contents in the gypsum boards was insufficient to have any appreciable effect on the signal returned. The ability to independently measure the moisture content of several layers with a single scan was also examined, but the data suggest that more work is needed to accomplish this goal.