KfW Energy-Efficient House

KfW Efficiency House is an energy efficiency standard for buildings defined by the Kreditanstalt für Wiederaufbau (KfW) that is used as a basis for granting promotional loans and repayment subsidies. The designation combines the abbreviation “KfW” with a numerical value that expresses the building’s annual primary energy demand as a percentage of the statutory reference building under the Building Energy Act (GEG). A KfW Efficiency House 55 therefore requires a maximum of 55% of the reference building’s primary energy demand-the lower the number, the more efficient the building.

The Efficiency House Levels and Their Requirements

KfW currently distinguishes the following levels (as of 2024/2025): Efficiency House 40: 40% of the reference building’s primary energy demand - highest level, corresponds to a nearly zero-energy building. Efficiency House 55: 55% - standard for subsidized new construction (KfW 297/298). Efficiency House 70, 85, 100, 115: Levels for retrofits of existing buildings under the Federal Funding for Efficient Buildings (BEG). In addition, there is the special category Efficiency House Monument (EH Monument) for historically protected buildings, where the requirements are less stringent due to grandfathering provisions. In addition to primary energy demand, the heat loss through the building envelope (surface area) must also comply with a limit value.

Verification and Energy Efficiency Experts

Verification of the Efficiency House level must be provided by a certified energy efficiency expert (iSFP consultant or BEG energy consultant). Before the renovation begins, this expert prepares the plans, and after the measures are completed, they issue the confirmation of completion (BnD), which is required for the disbursement of the repayment subsidy. Without this verification, no funding is available. The list of certified experts is available from the German Energy Agency (dena).

Typical Renovation Measures by Energy Efficiency Level

The more ambitious the target level, the more extensive the required measures. For an existing building from the 1970s, the following generally applies:

• EH 115: Replacement of the heating system with an efficient system (heat pump, pellets), roof insulation if necessary
• EH 100: Additional insulation of the basement ceiling and facade insulation (ETICS or core insulation)
• EH 85: Replacement of all windows, insulation of the top floor ceiling
• EH 70: Comprehensive building envelope renovation plus controlled residential ventilation
• EH 55 / EH 40: Full renovation to new-construction standards, often achievable only through core renovations

The choice of level determines the investment costs and the available repayment subsidy. KfW supports higher levels with higher subsidies: EH 85 receives a 5% subsidy, EH 55 receives 15%, and EH 40 receives 20% of eligible costs (up to the respective loan ceiling).

Significance in Real Estate Buying and Selling

A certified KfW Efficiency House has a clear advantage on the market: Buyers can benefit from more favorable financing terms (KfW subsidy loan), energy costs are predictably low, and the building already meets future energy requirements today. When selling an Efficiency House, the Efficiency House rating should be stated in the listing and verified by the energy performance certificate-this increases the property’s appeal and can positively influence the purchase price.

For investors, the energy efficiency rating is also relevant to rentability: Energy-efficiently renovated apartments command higher rents (lower utility costs for tenants despite higher base rent) and have a lower vacancy rate. As part of the discussed rental law reforms, a stronger link between rent increases and energy efficiency classes is also foreseeable.

Practical Tip for Property Owners in Nuremberg and Franconia

In Nuremberg and the Franconia metropolitan region, there are numerous older buildings that can be upgraded to Energy Efficiency Class 70 or 85 through comprehensive energy-efficient renovation-a worthwhile investment that both saves on heating costs and increases property value. Typical older buildings from the 1950s to the 1970s in Nuremberg (e.g., in Langwasser, Gibitzenhof, or Gebersdorf) often have primary energy requirements of 200-300 kWh/(m²a)-a full renovation to Efficiency House Level 70 cuts this figure in half and reduces heating costs accordingly.

At my-home.de, we know the market and can assess which Efficiency House level is achievable for a specific property and which subsidies are worthwhile. Ask us about historic preservation properties in Nuremberg’s Old Town-here, the special EH Monument level applies with adapted requirements, enabling subsidies without compromising the historic fabric.

Frequently Asked Questions

What is the difference between the energy performance certificate and the Efficiency House rating?

The energy performance certificate is a legally required document for all residential buildings and indicates energy consumption or demand in energy efficiency classes (A+ to H). The Efficiency House rating is a KfW-specific funding standard that exceeds the legal minimum standard and must be demonstrated to receive funding.

Can I retrofit an older house to meet the KfW Efficiency House standard?

Yes. The KfW programs for retrofitting existing buildings (BEG Residential Buildings, KfW 261) support exactly that. Depending on the building’s initial condition and the target Efficiency House rating, extensive measures regarding insulation, windows, heating, and ventilation are required. An iSFP (individual renovation roadmap) helps plan the renovation in phases.

Does a KfW Efficiency House increase a property’s resale value?

Generally, yes. Energy-efficient buildings command higher purchase prices and rents, as buyers and tenants anticipate lower operating costs. Studies show that the premium can range from 5% to 20%, depending on the region and energy efficiency class.

How long is the Efficiency House rating valid after completion?

The Efficiency House rating itself has no formal validity period-it describes the building’s condition at the time of completion or renovation. The energy performance certificate, which verifies the rating, is valid for 10 years. If structural changes are made (e.g., an addition, attic conversion, or heating system replacement), the primary energy demand changes and a new energy performance certificate is required. For the subsidy application itself, the subsequent validity is irrelevant-what matters is the confirmation of completion (BnD) immediately after the renovation is finished.

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