Ventilation airflows are an essential component of Passive House building performance, delivering the fresh, hygienic indoor air at the heart of Passive House goals. As buildings grow in size, ventilation duct leakage grows in importance, and successfully commissioning a system with airtight ducts with minimal leakage becomes essential to obtaining Passive House Certification. Focusing on multifamily buildings, this presentation uncovers the difficulties, defines the targets, and provides strategies for success…