Passivhaus

A rigorous voluntary building energy standard originating in Germany requiring extremely high levels of insulation, airtightness, triple glazing, and mechanical ventilation with heat recovery (MVHR) to achieve a space heating demand of ≤15 kWh/(m²·yr). Passivhaus buildings are comfortable, healthy, and low-running-cost. Certifying an extension to Passivhaus standard is rare but increasingly achievable with modern products.