A rigorous, performance-based energy-efficiency building standard focused on ultra-low heating/cooling demand through airtightness, insulation, and heat recovery - rather than points-based credits. Unlike LEED or BREEAM, which award credits across many categories, Passivhaus certifies a building against a small set of hard, measurable performance thresholds - primarily heating/cooling demand and airtightness (measured via a blower-door test). Because the standard is so sensitive to construction detailing, Passivhaus projects typically demand tighter coordination between the Revit model and the actual as-built envelope than a typical green-building certification.