Passive House Standard

Passive House Standard - The Passive House Standard is an energy efficiency standard for buildings in which the heating energy requirement is a maximum of 15 kWh per square meter per year. Developed and defined by the Passive House Institute in Darmstadt, it describes buildings that require virtually no conventional heating system and meet most of their heating needs from passive sources such as solar radiation, body heat, and waste heat from appliances.

The Five Basic Principles of the Passive House

The Passive House Standard is based on five coordinated design principles that together enable extremely low energy consumption:

Excellent thermal insulation: All components of the building envelope-exterior walls, roof, and floor slab-achieve U-values of 0.15 W/(m²·K) or better. This requires insulation thicknesses of 25 to 40 centimeters, depending on the material and component. The insulation must be installed seamlessly and uniformly.

Absence of thermal bridges: Structural thermal bridges-i.e., areas where heat escapes more quickly to the outside-are consistently avoided or minimized. The thermal bridge loss coefficient must not exceed 0.01 W/(m·K). This applies in particular to window connections, balcony slabs, and building corners.

Airtight building envelope: The air exchange rate during a pressure test (blower door test) must not exceed 0.6 per hour at a pressure difference of 50 pascals. A carefully constructed airtight envelope prevents uncontrolled heat loss through joints and leaks.

Controlled residential ventilation with heat recovery: A central ventilation system extracts stale air and supplies fresh outdoor air. A heat exchanger recovers at least 75 percent of the heat from the exhaust air. The ventilation system replaces traditional window ventilation and ensures consistently high air quality.

High-quality windows and glazing: Triple-glazed windows with a U-value of 0.80 W/(m²·K) or better and thermally insulated frames are standard. The windows are designed in terms of size and orientation to maximize solar gains in winter.

Costs and Comparison with the KfW Efficiency House

Experience shows that the additional costs for the Passive House standard are 10 to 15 percent higher than for a building meeting the current GEG minimum standard. For a single-family home with 150 square meters of living space, this amounts to approximately 30,000 to 50,000 euros. This investment pays for itself through the savings on heating costs-a Passive House requires only about 1.5 liters of heating oil equivalent per square meter per year, compared to 5 to 8 liters for a conventional new build. Compared to the KfW Efficiency House 40, the Passive House standard imposes similarly strict requirements but places greater emphasis on the building envelope and the ventilation system, whereas the KfW system also places greater weight on building services.

Passive House Standard and Property Value

A certified Passive House offers clear marketing advantages: The energy performance certificate displays excellent ratings (typically energy efficiency class A+), which increasingly serves as a selling point for buyers and tenants. Especially in times of rising energy prices, operating costs are a key decision-making factor. Buyers choosing between a conventional new build and a passive house can directly calculate the annual heating cost savings-often ranging from 1,500 to 3,000 euros-and are willing to pay a premium for it.

In real estate appraisals, a very good energy performance certificate is increasingly reflected in higher appraisal values. The Building Energy Act (GEG) requires the disclosure of the energy performance certificate for certain transactions; an A+ rating is a strong selling point that we actively leverage in our marketing.

Practical Tip for Nuremberg and Franconia

In the Nuremberg metropolitan region, numerous Passive House projects have already been completed-both in single-family homes and in multi-story apartment buildings. The Franconian climate, with its cold winters and warm summers, is well-suited to the Passive House concept, as the ventilation system efficiently recovers heat in winter and prevents overheating in summer through night cooling and good insulation. We recommend that homeowners consult a certified Passive House designer when planning a Passive House in Nuremberg. Certification by the Passive House Institute is voluntary, but it enhances quality assurance and can increase resale value.

When selling Passive House properties in Nuremberg and the surrounding area, we recommend communicating the low energy consumption in concrete figures: How much do you pay monthly for heating, electricity, and hot water in a passive house compared to an older building? This transparency convinces prospective buyers far more than abstract technical terms.

Frequently Asked Questions

Does a passive house no longer need any heating at all?

A passive house does not require a conventional heating system with radiators, but it cannot function entirely without a heat source. Residual heat is usually provided by a small reheating coil in the ventilation system-often in the form of a low-capacity air-to-water heat pump. On the coldest days of the year, just a few hundred watts are enough to maintain a room temperature of 20 to 22 degrees.

Can I open the windows in a passive house?

Of course. The controlled ventilation system ensures basic ventilation, but the windows can be opened at any time. In the summer, opening the windows for nighttime cooling is even expressly recommended. Only in the winter do we recommend keeping the windows closed so as not to compromise the efficiency of heat recovery.

Is a passive house worth it given current energy prices?

The cost-effectiveness of a passive house has improved significantly with the rise in energy prices in recent years. At current gas and electricity prices, the additional costs are typically recouped within 15 to 20 years. In addition, KfW subsidy programs offer low-interest loans and repayment grants for particularly energy-efficient new buildings. In the long term, owners benefit from largely being independent of rising energy prices and a high resale value.

What subsidy programs are available for the Passive House standard?

The Passive House standard generally meets the requirements for the KfW Efficiency House 40 (BEG Residential Buildings). In addition, grants from the Bavarian State Land Credit Institution (BayernLabo) and municipal subsidy programs may be available. It is recommended to consult with a financial advisor early on, as subsidy programs are regularly updated.

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