Passive House Standard for Municipally Owned and Municipally Used Buildings in Frankfurt am Main

In 1990, Frankfurt joined the “Climate-Alliance of European Cities” and developed an energy concept focused on energy efficient buildings and cogeneration of heat and power. Even if living space (by 15%) and office space (by 80%) have increased, CO₂ emissions were still reduced by 10% between 1990 and 2008. In addition to the support for cogeneration of heat and power (CHP), the city focuses on the dissemination of the Passive House Standard.

The aim of the policy is to promote the Passive House Standard as the new building standard in Frankfurt am Main. This is to be achieved through the obligation that buildings built by the municipality or for its use have to be built in Passive House Standard. Also the ABG Frankfurt Holding - a city owned real estate company - is supporting this measure for its own housing stock. Additionally, the City promotes the standard via contracts: whenever municipal property is sold to a private person as a construction site, the buyer has to build with PHS.
If PHS is not possible (a justification is required in that case), the energy consumption of the building has to be 30% below the national MEPS (EnEV 2009).
Through the introduction of this self-obligation for the public sector, the City of Frankfurt is leading the way and setting a good example in terms of ultra-low energy buildings. Therefore, the aim of the policy is ultimately to induce replication in the private sector by raising public awareness of the PH concept, demonstrating to investors its economic viability and other benefits (e.g. improved working conditions due to better indoor climate), and also – by way of increasing the demand for passive houses – incentivising the construction industry to further advance their PH construction skills and technologies.

The policy is implemented on a local level.

The sectoral focus is the residential and public sector (in the case of municipal property sold to private investors possibly also commercial sector)

• Passive House Standard
• Ventilation System
• Windows

The targets are the promotion of the PH Standard and the use of CHP. This is to be achieved through information campaigns and legal requirements. The City is therefore obliged to build in PH standard, and if this is not possible, the new building has to be at least 30% below EnEV. Also, citizens should be made aware of the opportunities of the PH Standard, its economic feasibility and the benefits offered by passive houses, such as energy cost savings and increased comfort levels.

Relevant target groups

• General management company
• Construction company
• System supplier
• Architect
• Engineering consultant
• Installation contractor
• Wholesale company
• Manufacturer of prefabricated houses

Direct beneficiaries

• User

• Governmental actor

Indirect beneficiaries

• Manufacturer

Relevant barriers

• Economic and financial barriers: Several tests have shown the potential of the PHS, and have proven that it is economically feasible to stipulate the PHS. Over the building’s life cycle, the significantly reduced operating costs justify the higher investment in the beginning.
• Knowledge and information barriers: Through the creation of tangible demonstration buildings, investors, future building owners and also tenants are informed about the benefits (monetary and comfort-wise) of passive houses. They are also assured that such buildings offer the same functionality and safety as conventional ones and higher comfort levels at the same time.
• Lack of interest and motivation in energy efficiency-improvement: By increasing the demand for passive houses, the actors in the construction industry are reassured (or made aware for the first time) that there is a market demand for such ultra-low energy buildings.

Relevant incentives

• Saved energy costs:
• Improved reputation:
• Increased (re-sale) value of the property:
• Contribution to protection of the environment:

• KLIMAtours (Climate Tours): Site visits to the most energy-efficient homes and office buildings are organised by the Energiereferat for building professionals and interested experts/decision makers; the tours can be customised according to the respective interests
• “Energetische Sanierung von Gründerzeitbauten in Frankfurt” (Energetic Refurbishment of Wilheminian Style Buildings in Frankfurt). 
• “Energieforum Banken und Büro” for better EE planning of office buildings. The Commerzbank Tower is a good example for possible improvements in building planning, if investors, planners and the Energiereferat work together on optimising strategies. 
• Ecological rent index: Integration of energy demand / thermal characteristics in the rent index, thus allowing landlords to charge higher basic rents for buildings with low energy costs.
• Consumption-based Energy Performance Certificates for tenants (Energieverbrauchsausweis für Mieter)
• TIP (Total Integrated Power): TIP is the attempt to induce the co-operation between municipal institutions, companies, consulting and science. From the first step of the planning phase, energy efficiency issues shall be discussed and planned together.
• Guidelines for cost-effective construction (Leitlinien zum wirtschaftlichen Bauen) www.bigee.net/s/aj7pm1
• List of qualified energy consultants
• Different measures to motivate home owners to perform a home energy audit
• Cariteam: Training of unemployed persons to become home energy consultants, and free home energy advice for low-income households

Furthermore, a Department for Energy Management has been set up within the City Construction Office. The department provides a number of services (e.g. energy controlling, automated consumption monitoring, optimised building operation, etc.) in order to minimise the energy and water consumption in municipal buildings. Between 1990 and 2009, net savings of € 83.4 million have been achieved through energy management (www.bigee.net/s/ng4nv7).

The policy includes innovative instruments/elements and combines them in an innovative package:
In order to be ahead of schedule, Frankfurt promotes the EU guideline for Nearly Zero Energy Buildings to come in 2020 at a very early stage and is creating a building stock that is not only more energy- and resource-efficient, but also performs well economically.
Since municipalities in Germany cannot mandate stricter general energy efficiency standards for buildings than the national law, the City uses the two options it has available: mandating the strict PHS for its own buildings, and for buildings constructed on land that the City sells, via the sales contracts. This works well as land is scarce in the Frankfurt area.
The policy is part of a wide range of energy efficiency improvement measures for buildings promoted in the City of Frankfurt.

In countries where local authorities have the legal possibility to do so, the policy can be optimised by setting the Passive House Standard as standard for all new buildings, municipal or private.

Before the policy was implemented, evaluations of the energy performance and the lifecycle costs of existing passive houses were made or considered with the result, that the investment will be paid back after a maximum of 30 years from saved heating costs, and that over 50 years costs of over €75,000 could be saved in PH homes.

Agencies or other actors responsible for implementation
The City’s Energy Department was instrumental in collecting this evidence and drafting the policy. City of Frankfurt’s Construction Office has the task to implement it for the municipal buildings.

Funding
The promotional bank of the Federal Republic of Germany (KfW) provides soft loans for passive houses.

In the beginning of the 1990s, Frankfurt started to build public buildings like kindergartens and housing estates with heating energy demand parameters of 75 kWh/m²/yr but soon improved this standard to PHS with heating energy demand parameters below 15 kWh/m²/yr. In 1998/1999, the first single family houses were constructed with PHS and another important project was the construction of 19 housing units with PHS realised through the FAAG corporation, which is a subsidiary company of ABG Frankfurt Holding. This project was the activator for ABG’s decision to construct new buildings in PHS only. So far 800 dwellings have been constructed, are under construction or planned. In 2004 and 2007, new schools in PHS design were constructed, belonging to the first ones in Germany.
In 2007, this resulted in the enactment by the City Council (Parliament) that all new municipal buildings have to be designed and built in accordance with the PHS. This requirement was justified through better indoor air quality and cost-effectiveness over the life cycle. Investors who buy municipal property are also obliged to build in PHS wherever possible, otherwise 30% below the EnEV. Frankfurt’s declared aim is to become “Passivhaus-Bundeshauptstadt” (Federal Capital of Passive Houses) and therefore it has established the PHS as its standard construction method.
The City of Frankfurt Construction Office was assigned the task of implementing the standard in new municipal buildings.
Costs for passive houses have been assessed in already built dwellings and it has been discovered, that due to yearly energy savings, tax advantages and better interest rates with the KfW, passive houses are the cost effective option in the long run.

Quantified target
The target is for the ABG Frankfurt Holding to have realised the construction of 1,300 new PHS apartments by 2013.

Actors responsible for design
Energiereferat der Stadt Frankfurt am Main (Department of Energy of the City of Frankfurt)

Actors responsible for the implementation
Hochbauamt Frankfurt (City of Frankfurt Construction Office)

Monitoring
There is a monitoring system in place tracking data necessary for evaluation, such as capital, operating and environmental follow-up costs.

Evaluation
There is no evaluation available for the policy as a whole. However, some example buildings have been evaluated.

• Dynamic market transformation and/or innovation: The policy sets a voluntary minimum energy performance standard at a very high level of energy performance for all new municipally owned and used buildings. This is also required of private investors when the City sells land for construction. In order to further promote the PHS, several measures have been developed, such as a list of qualified contractors and energy advisors and a list of energy-efficient appliances, both provided by the Energiereferat, an ecological rent-index, an initiative called “The future of your House”, Frankfurt energy saving campaign etc. Also, the City is operating an informative webpage in order to give a comprehensive overview on possibilities to improve the energy performance of dwellings or why it is worth building a passive house (costs and benefits). Employees of the Energiereferat also offer face-to-face consultancy. The City of Frankfurt Construction Office is responsible for the implementation of the policy and has to promote sustainable building measures, which should result in a sustainable and ecological architecture. The buildings have to be in balance between economy and ecology and finally Plus-Energy Houses i.e. buildings that produce more energy than they consume, shall be constructed. It is planned to implement a certification system for municipal buildings regarding their sustainability and stable value. Important is the minimisation of total costs i.e. capital, operating, and environmental follow up costs, over the buildings lifecycle. With the help of an assessment programme, municipal building quality should become measurable and comparable. Through this action, the chances for a high-profile architecture and resource-efficient materials and constructions and sustainable technical equipment are improving. Frankfurt was the first municipality in Germany to join the “Deutsche Gesellschaft für Nachhaltiges Bauen” (German Association for Sustainable Construction).
• Creating Spill-over effects: The awareness raising and motivational effect of the public sector setting a good example is very likely to induce replication in the private sector. Through the creation of a significant number of demonstration buildings, the accompanying information and advice measures showing the cost-effectiveness of the PH concept, and also the increased knowledge and skills in the construction industry that result from the increased demand for PH, it can be expected that also more and more private investors will begin to see the benefits of building in accordance with the PHS.
• Avoiding lost opportunities: The policy clearly aims to avoid lost opportunities in new construction, since every building just meeting the minimum energy performance standards is a lost opportunity to maximise efficiency and minimise energy consumption. The city tries to achieve the maximum energy savings it can achieve today by making the standards mandatory for the city itself and when selling land. In order to promote the PHS to other groups, the “Energiereferat” in Frankfurt drafts and distributes brochures. Additionally, it tries to keep the webpage up to date for the latest information.

With the PHS, co-benefits like fresh air without open windows can be achieved. In schools this is good for the learning atmosphere, because outside noise is mostly eliminated and it can be good for allergic persons too. The ventilation system filters the fresh air and therefore pollen and dust have hardly any chance of getting into the building.

No information on the overall energy savings expected from the City’s PH standard is available.

An example house of 162 m² is expected to achieve end-use energy savings (heating and warm water) of approximately 11,000 kWh/yr compared to a house built with EnEV 2009 Standard (Stadt Frankfurt am Main 2011, p. 4).
According to the Füßler Survey, the primary energy demand for the 162 m² example PH is around 9.000 kWh/yr lower than in the EnEV house (6.626 vs. 15.698) (Füßler 2010). This corresponds to 27.7 compared to 73.7 kWh/m²/yr. The end-use energy demand is almost 11,000 kWh lower than in a comparable EnEV house.

No information on the overall energy savings achieved by the City’s PH standard is available.
However, the Riedberg school is saving 8.5 litres of heating oil per m² and year (1.5 instead of 10 l) (Stadt Frankfurt am Main 2009, p. 10).

For the example house of 162 m², the construction costs are assessed at €1,914 per m² compared to €1,784 per m² for a standard EnEV 2009 house. This translates to additional costs of approx. € 21,000 for the whole house i.e. an incremental construction cost of 6.71%. The interest rate for the PH was 3.05 over a 10 year period (KfW preferential loan), not available for EnEV (Stadt Frankfurt am Main 2011, p. 4).

The Riedbergschule equated to a total project cost of €16.7 million and to €1,110/m². The additional costs compared to EnEV 2004 -30% were 5.3%.

According to the exemplary comparison assessment of an EnEV 2009 and a PHS dwelling of 162 m², the cost savings total € 75.000over 50 years (Stadt Frankfurt am Main 2011, p. 5).
The total costs (capital and operation/energy) for the PHS-School in Riedberg can be reduced from €1.43 to €1.32 million/yr. Heating costs can be reduced by €67,000 from €75,000 to €8,000/yr compared to a usual EnEV building (Table 2).
The Grundschule Preungesheim (Elementary School Preungesheim) can reduce its annual costs compared to EnEV Standard building from €1.71 to €1.63 million. The reduction in heating costs only are €83,000/yr. A table for an overview of total costs is attached (next table).

The example house of 162 m² is supposed to save more than €75,000 over a 50 year period and is therefore cost effective (Stadt Frankfurt am Main 2011, p. 5).
The Grundschule Preungesheim saves annually €88,000 by being built in PHS compared to EnEV. The higher investment costs will pay back after 14.8 years (see the first table).
The Riedberg school saves €108,000 annually with the PHS compared to EnEV and the additional costs will pay back after 4.3 years.