Efficiency house

The term efficiency house is an energy standard for residential buildings that the Kreditanstalt für Wiederaufbau ( KfW ) introduced.

Efficiency houses are buildings that are characterized by their particularly energy-efficient construction and building technology and that achieve a higher level of energy efficiency than required by law. The energy efficiency of a building is measured based on the transmission heat loss (heat loss through the building envelope such as insulation and windows) and, based on this, the annual primary energy requirement (the energy source used has a major influence). The currently valid Energy Saving Ordinance (EnEV) defines the determination of reference values for these key figures . Based on the EnEV 2009, they are assigned to various state funding standards of KfW. Various KfW efficiency house standards apply to new buildings and energy-efficient renovation of existing properties.

Building standards

Efficiency houses are available in different energy standards . The starting point is the specifications of the EnEV, with which a so-called reference house is calculated for every construction or renovation project. This reference house has the same geometry, usable area and orientation as the building to be constructed and uses reference values from the EnEV for every component (e.g. wall, window, door). For its calculations, KfW also refers to the 2009 requirement level in accordance with the increased requirements of the EnEV in 2016. The reference building procedure results in building-specific reference values for the transmission heat loss and the annual primary energy requirement on which the energy standard is based. A KfW Efficiency House 100 may therefore only consume as much primary energy as the reference house (EnEV 2009). In addition, the transmission heat loss may not exceed 115% (EnEV 2009). The smaller the number, the more energy-efficient the house is. The efficiency house 40 has the lowest energy requirement, the primary energy requirement of which is only 40% of the reference house (EnEV 2009).

Permissible maximum values based on the EnEV 2009 reference house (new construction and renovation)
(as of December 2015)
default	Primary energy demand	Transmission heat loss
Efficiency house 40	40%	55%
Efficiency house 55	55%	70%
Efficiency house 70	70%	85%
Efficiency house 85	85%	100%
Efficiency house 100	100%	115%
Efficiency house 115	115%	130%
Efficiency House Monument ¹	160%	175%
¹ Target value for listed buildings, this can be deviated from under certain circumstances.

Although the amended Energy Saving Ordinance EnEV 2014 has been in force since May 1, 2014 , more stringent energy requirements for new buildings only came into force on January 1, 2016 (EnEV 2014 with changes from 2016). However, KfW continues to base its calculations on the 2009 requirement level and compares the requirements with the reference house according to the EnEV 2009 version. Therefore, the KfW Efficiency House 70 funding for new buildings had to be dropped.

In addition to the KfW funding standards, there is the “Efficiency House ” seal of approval from the Deutsche Energie-Agentur GmbH (dena) . The seal confirms the KfW standard through a quality-assured process.

In contrast to the KfW efficiency house standard , the passive house standard does not specify a relative value related to the EnEV, but rather defines a living space-related maximum heating requirement of 15 kWh / m²a or a maximum heating load of 10 W / m² in order to be able to do without classic building heating . This corresponds to around 20% of the value of an EnEV reference house of a single-family house with 120 m². As a rule, a passive house as an efficiency house can be funded by KfW.

Subsidies for residential buildings

The Kreditanstalt für Wiederaufbau (KfW) offers building owners and homeowners low-interest loans and grants for energy-efficient renovation and energy-efficient new construction of residential properties with the programs "Energy-efficient construction" (program 153) and "Energy-efficient renovation" (programs 151, 152, 430). The amount of funding depends on the building's energy efficiency . In addition, KfW promotes individual measures to improve the energetic quality of existing residential buildings.

Funding levels for new and old buildings

The subsidy increases with the energetic quality of the building and a distinction is made between new and old buildings. Since it is much easier to achieve a good efficiency standard in a new building than in an old building, the EnEV defines the permissible primary energy requirement of the reference building as the permissible primary energy requirement of the reference building (permissible value as of January 1, 2016 reduced by 25% compared to 2009) and 115% in the old building (since January 1, 2016) January 2016, previously 140%); monuments are an exception. Since state funding is only possible as an additional incentive for better standards, only standards 40 Plus, 40 and 55 apply to new buildings. For new buildings, funding for an efficiency house 70 - although only 5% better than the EnEV minimum requirement - was eligible for application possible between January 1st and April 1st, 2016. For the energetic renovation of existing properties there are standards 55, 70, 85, 100 and 115 as well as monument. Individual measures are also funded.

For the new building, subsidies are possible as loans with a repayment subsidy. For a KfW Efficiency House 40 Plus, 40 and 55, the interest rate is 0.75%. For new buildings with the KfW Efficiency House Standard, there is a loan with up to 25% repayment subsidy at an interest rate of 0.75%, regardless of the loan term, fixed interest rates and selected repayment-free start-up period. (As of January 2020)

Energy-efficient renovations of existing buildings are promoted with low-interest loans with 0.75% interest. Depending on the standard reached, different repayment subsidies are possible; the Efficiency House 40 Standard and Efficiency House 40 Plus Standard do not apply here. Alternatively, a subsidy without a loan can be made for renovations, the subsidy is between 20% - 40% of the eligible costs up to 10,000 euros - 48,000 euros per residential unit, depending on the KfW efficiency house type achieved. (As of January 2020)

Funding amount for KfW efficiency houses (EnEV 2014 with changes from 2016)
As of January 2020
default	New building	Renovation ¹
KfW Efficiency House 40 Plus	Loan of up to 120,000 euros with a repayment subsidy of 25%
KfW Efficiency House 40	Loan of up to 120,000 euros with a repayment subsidy of 20%
KfW Efficiency House 55	Loan of up to 120,000 euros with a repayment subsidy of 15%	Loan of up to 120,000 euros with a repayment subsidy of 40% or an investment subsidy of 40%
KfW Efficiency House 70		Loan of up to 120,000 euros with a repayment subsidy 35% or investment cost subsidy 35%
KfW Efficiency House 85		Loan of up to 120,000 euros with a repayment subsidy of 30% or investment cost subsidy 30%
KfW Efficiency House 100		Loan of up to 120,000 euros with a repayment subsidy of 27.5% or investment cost subsidy 27.5%
KfW Efficiency House 115		Loan of up to 120,000 euros with a repayment subsidy of 25% or investment cost subsidy 25%
KfW Efficiency House Monument		Loan of up to 120,000 euros with a repayment subsidy of 25% or investment cost subsidy 25%
Individual measures		Loan of up to 50,000 euros with a repayment subsidy of 20% or investment cost subsidy 20%
¹ The subsidy variant is only available for one- and two-family house owners or private owner associations.

There are also federal state-specific funding programs and accompanying funding for the preparation and implementation of efficiency measures on the building.

Funding application

Funding must be applied for before construction begins. Loans are to be applied for through the house bank, the investment grant directly at KfW. In order to receive KfW funding for an efficiency house, a certified energy advisor must be involved in the project. It confirms compliance with KfW's minimum technical requirements. This confirmation is required by builders and home owners to apply for funding. In addition to the energy-related planning, the energy consultant also provides professional construction supervision. With a KfW Efficiency House 40 and 55, this is always required to receive funding. For KfW funding, the energy advisor has to be entered in the list of energy efficiency experts for federal funding programs since June 1, 2014.

Changes in April 2016

Energy standards for new buildings (as of 2016)

The changes to the minimum requirements of the EnEV as of January 1, 2016 have an impact on the KfW funding program. The KfW Efficiency House 70 in the new building is no longer funded, as the reference by KfW to the reference house according to EnEV 2009 would only be about 5% better than the minimum standard of the valid EnEV 2014 with changes in 2016. An alternative verification procedure for the KfW Efficiency House 55 was implemented to make it easier for the builder to prove it. The verification by comparison with component reference values saves extensive calculations. At the same time, the amount of funding was increased, the maximum funding contribution per residential unit was doubled from € 50,000 to € 100,000. The maximum selectable fixed interest rate has also been increased from up to 10 years to up to 20 years.

In addition, a further level of KfW funding for new buildings was introduced, the KfW Efficiency House 40 plus. The KfW Efficiency House 40 plus must meet the requirements of the existing KfW Efficiency House 40 and also generate and store a significant part of the energy requirement directly on the building using a so-called “Plus Package”. The "Plus Package" includes the following four criteria:

An electricity generating system based on renewable energies, for example through photovoltaic systems, small wind turbines or combined heat and power systems that are operated 100% with renewable energies.
A stationary battery storage system as electricity storage ensures independence from external energy suppliers.
A ventilation system with heat recovery with a heat recovery rate of at least 80%.
A visualization of power generation and power consumption via a corresponding user interface, for example through online monitoring.

Web links

Individual evidence

[1] KfW (Reconstruction Loan Corporation)

[2] The KfW Efficiency House

[3] EnEV

[4] KfW Energy Efficient Renovation Program - Loan (Programs 151, 152)

[5] KfW Energy Efficient Building Program - Credit (Program 153)

[6] KfW program energy efficient renovation - investment grant (program 430)

[7] Energy efficiency experts