Green House, Zero Energy Consumption, "Maison Passive" in Paris Suburbs, Credit Architect: Micha Witzmann, Detail Back, Doors, Patio. "The Passive House, often called "house without heating, based on a design concept very low power consumption, based on the use of passive heat of the sun on a very high insulation (walls, windows, etc. ... ), the absence of thermal bridges, high airtightness and controlled ventilation. A passive house uses 90% of heating energy in less than an existing building. And 75% less than a house newly built by the current thermal regulations (RT2005). Whatever its mode of construction and its location, a passive house, with all the modern comforts, needs no more than 15 kWh per m2 per year (1.5 liter per m2 per year of oil equivalent) by heating. The passive current achievements show that this definition is valid for regions with a harsh climate or southern climate or in the whole area between Madrid and Stockholm. A passive house costs only 10 to 25 euros per month for heating. This is significantly lower than low energy house (40 to 65 kWh / (M2A), depending on climate zone). And yet the comfort is much better! For heating, passive house uses all available sources of heat (sun, people, etc..). The windows and highly efficient insulation of exterior walls, roof and floor can keep the heat inside. The fresh air is supplied by a "controlled mechanical ventilation" (CMV) turbofan audible (25dB), which recovers heat from outgoing air to warm incoming air.