Building for a green future

The building sector is responsible for around 17 percent of all greenhouse gas emissions in Vienna, a number which should be reduced by two percent every year under the Smart City framework strategy of the City of Vienna. In order to achieve this objective, buildings must be supplied with energy in a more environmentally-friendly way, while at the same time being made much more energy efficient.

The Guideline of the Austrian Institute for Structural Engineering (OIB Guideline) and the building regulations of the provinces make up the legal framework here, regulating the minimum technical requirements for technical building services (e.g. e-charging points) and heating systems. The use of fossil fuels in buildings should be gradually replaced by environmentally-friendly alternatives such as district heating or PV systems. Wien Energie already supplies 380,000 households with district heating today. We are also working on turning Vienna into a city of solar power and are committed to expanding the infrastructure for private charging points for electric cars.

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Background information

Environmentally harmful heating systems and inefficient structures in old buildings are primarily responsible for the high level of CO2 emissions produced in the building sector. The legal framework conditions required to bring about change here are set out in Vienna by the OIB Guideline and Vienna’s building code, the latter in turn being legally based on the EU’s Building Directive.

The EU’s Building Directive was amended in 2018 and contains, among other things, regulations on permitted heating systems, limit values regarding the energy efficiency of buildings and requirements for e-mobility in car parks. Member States must have largely transposed the directive into national law by 2020.

The EU’s Building Directive has been implemented in Austria through the OIB Guideline, which sets out the technical guidelines applicable throughout the country on energy efficiency and the use of renewable energy sources in buildings. While it is not an actual piece of legislation, per se, the provinces have undertaken to adopt the Guideline in their respective building regulations.

The building sector saw a number of far-reaching changes as a result of the 2019 amendment to Vienna’s building code, the most relevant of which being the decentralised ban on gas-fired heating systems in new buildings and when renovating buildings, as well as the new regulations on energy plans (or climate zones).

  • The ban on gas-fired heating systems in new buildings and when renovating buildings is by far the most comprehensive change. However, if gas heating is the only possible option for technical or economic reasons, compensatory measures must be taken, such as installing PV systems or a heat pump, or implementing energy efficiency measures.
  • The new regulation pertaining to these energy zones states that the city council can adopt energy concepts for certain areas in Vienna. Only highly efficient alternative heating systems may be used in these areas, including decentralised energy supply systems based on renewable energy sources, micro-cogeneration plants, district heating and heat pumps. Energy zones are to be gradually expanded to cover the whole of Vienna, thereby ensuring an environmentally-friendly supply of heat to the city.
Michael Cerveny

“Vienna’s building regulations, which also including zoning, and its programme of housing subsidies mean that the city has made use of some key instruments to manage the heating revolution. If we want to achieve the climate protection targets set as part of the framework strategy of the Smart City Vienna, investment needs to be made both in cutting heat consumption as well as replacing fossil-fuel-powered heating systems with district heating or renewable energies. Wien Energie has a key role to play here.”

Michael Cerveny, Senior Expert Urban Innovation

Our demands

Vienna’s building regulations are some of the most important regulatory frameworks when it comes to reducing greenhouse gas emissions in the heating sector. However, Wien Energie believes that some adjustments need to be made to promote the wider use of renewable energies and to meet the obligations of the EU’s Building Directive as regards e-mobility:

Photovoltaics is one of the most important and promising sources of renewable energy in urban areas, which is why particular attention must be paid to fully exploiting the PV potential, especially in new buildings. Vienna’s building regulations stipulate that PV systems must be installed on the roofs of non-residential buildings. In practice, however, it is not always possible to comply with this requirement as a result of technical difficulties. As such, if a PV system cannot be installed on the roof of a new building, it should be required in future for the obligation to be met at another suitable location.

The EU’s Building Directive states that a defined number of parking spaces must be equipped in such a way to enable a private charging point to be installed at any time. This requirement is not, however, sufficiently reflected in Vienna’s building code. Aside from generally implementing the directive, there are a number of points that are particularly important for Wien Energie:

  • Parking spaces in new and renovated residential buildings should be equipped in such a way that a charging point capable of 3.7 kW at the very least can be installed at any time.
  • In all other newly built or renovated buildings, it must be possible to retrofit every third parking space with a 3.7 kW charging point at any time. A 20 kW-fast charger should also be available if deemed necessary in view of the average length of time spent in the building (e.g. supermarket).
  • Ducts must be available for power and data lines to run from the meter to the parking space, and space must be also be reserved for electricity meters and transformers. In addition, the option of charging electric cars must be considered when calculating the building’s grid connection capacity, and there must be stable data connection in place for the charging process.

Further information

Your contact person

Micha Gruber
Micha Gruber

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