What is Passivhaus? "A Passivhaus is a building in which extra air recirculation is not necessary to create sufficient indoor air quality conditions—thermal comfort can be accomplished only by post-heating or post-cooling of the fresh air mass.” The world's fastest-growing energy performance standard is called Passivhaus. The main advantages of the standard are straightforward in theory: they call for the construction of buildings with exceptional airtightness and thermal performance when mechanical ventilation is utilized. The designer is forced to minimize the "Heating Demand" by using this straightforward and reliable method of structure design. A Mechanical Ventilation and Heat Recovery (MVHR) system then collects and distributes the heat produced internally.