Relative humidity levels are often ignored in homes despite the fact that unsuitable levels can be unhealthy, increase heating and cooling costs, damage building components, and affect comfort levels.
Research has shown that high-relative humidity levels also support the growth of dust mites, molds and bugs that can lead to increased allergy symptoms and reduce indoor air quality (IAQ). However, little to no measured data is available on actual indoor humidity levels in homes across the United States.
Concerned about the impact that relative humidity 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.
Three different regions are being targeted for the study – the warm, 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 selected HOBO U12 data loggers from Massachusetts-based Onset Computer Corporation.
The data collected from this study will support efforts already underway by the ASHRAE Standard Committee 160P on “Design Criteria for Preventing Moisture Damage in Buildings” and others to develop moisture modeling tools and related technical standards. These models and standards will help improve a home’s performance by minimizing conditions associated with high moisture levels. Test homes for this study are currently being identified, and most initial site visits and data logger installations should be complete by the beginning of this summer.
