Air barriers are essential to energy performance, comfort, and durability, yet most industry guidance focuses on achieving a blower-door number at final inspection rather than understanding how airtightness holds up over time. Earth Advantage, in partnership with NREL’s Building America program, conducted a multi-year study evaluating how common residential air-barrier materials and assemblies perform under real-world conditions. The research combined controlled exposure testing, field inspections, and follow-up blower-door results to identify which systems maintain airtightness and which degrade due to material, sequencing, or workmanship issues. This session distills the most actionable findings—resilient assemblies, vulnerable details, and practical installation methods that consistently deliver durable results. We will connect these lessons to Oregon’s evolving energy codes, incentive pathways, and QA/QC practices, offering guidance that builders, designers, and raters can apply immediately. Attendees will leave with a clearer understanding of how to specify, install, and verify air-barrier systems that perform well on day one and continue to perform years later.
