BOURNE, Mass. - Although unsuitable relative humidity (rh) levels in homes can be unhealthy, increase heating and cooling costs, damage building components, and affect comfort levels, there is little to no measured data available on actual indoor humidity levels in homes across the United States. Concerned about the affect that rh has on a building’s performance, the U.S. Department of Housing and Urban Development paired up with Steven Winter Associates Inc. (SWA), an architectural and engineering research and consulting firm, to gather temperature and humidity data in more than 50 homes across the country this summer.

Three different regions are being targeted for the study - the warm and humid Southeast, the cold Northeast, and the Pacific Northwest. To complete the study, household characteristic data will also be collected during the initial site-visit to the home, including occupancy levels, insulation levels, equipment efficiencies, envelope leakage, and duct leakage.

To monitor temperature and humidity levels, SWA engineers will use HOBO® U12 data loggers from Onset Computer Corp., Bourne, Mass.

The battery-powered devices will measure and record humidity levels around-the clock - even during power outages. The accompanying HOBOware® Pro software will convert the data into time-stamped graphs that can be displayed on a PC or Mac.

The data collected from this study is expected to support efforts already underway by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard Committee 160P on “Design Criteria for Preventing Moisture Damage in Buildings” and others to develop moisture modeling tools and related technical standards. Test homes for this study are currently being identified, and most initial site visits and data logger installations have already been completed.

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Publication date:06/30/2008