Case studies of three ultra-high performance residential envelopes monitored as part of the Building America program areexamined. Three occupied homes in the Pacific Northwest Marine climate were monitored for at least a year. Two homes met theEuropeanPassive House standard. Monitoring included total energy use, heating, cooling,DHW, roomtemperatures, and relativehumidity. The challenge of economically meeting very low design loads while meeting comfort expectations is discussed. Thehomes were all approximately 2000 ft² (186 m²) with three bedrooms and two baths. They all used slab-on-grade constructionwith either SIPS panels or double wall construction. The studies present a cost benefit analysis of the high performance envelopemeasures including high R-value building assemblies, ultra-tight air leakage control (less than 0.6ACH50), and high performance fenestration.Total energy use ranged to less than 20.5 kBtu (6,000 kWh) annually. Space conditioning represented less than 25% oftotal energy use while loads other than space conditioning and DHW were over 60% of total annual energy use.

Presented at Thermal Performance of Exterior Envelopes of Whole Buildings XII, December 2013