Weatherization, IEQ and Building Performance: Study Methodology and Pre-weatherization Baseline

Abstract

The accelerated rate of implementing energy-efficiency measures in residential homes is outpacing our knowledge of the potential impacts on the indoor environment quality (IEQ). To address both the occupant exposure and potential contributing factors, real-time data (temperature, %RH, CO2, CO, particulate matter, total volatile organic compounds, formaldehyde, radon) were collected in pre-weatherization homes during the 2012-2013 heating season. Average NO2 values were also collected using passive samplers. Participants were recruited from ongoing Weatherization Assistance Programs through partnerships with community action agencies located in North Carolina’s diverse mountain and coastal zones. Other data being collected for analyzing pre/post-weatherization differences, include participant activities, exhaust fan and blower door measurements, building features, and occupant characteristics (smoking, pets). Results for data from ten pre-weatherization homes at each location indicate the following: CO, formaldehyde, NO2, and radon below acceptable levels in all test homes, except one with high NO2; six homes, somewhat elevated TVOCs (five in the mountains); eleven homes, elevated PM2.5 (eight at the coast); three homes carbon dioxide above 1000ppm. Comparison of homes with and without forced air heating systems show significantly higher counts of particulate matter in homes with forced air systems: an order of magnitude more 0.3 mm and 0.5 mm particles; similar amounts of 1.0 mm, 2.5 mm particles; and 50-100% more 5.0 mm and 10 mm particles. Average values for outdoor samples at both locations indicate that all parameters are less than indoor values, except values for particle sizes 1.0 mm, 2.5 mm, 5 mm, and 10 mm at the coastal location. Additional analysis comparing data from two NO2 passive samplers and two wind speed sensors at WAMY study homes, showed good agreement (< 2ppb) for the NO2 samplers, and an average difference of 45% for the wind speed sensors.