Salzbug Municipality, Austria

The city of Salzburg is located next to the Prealps being one of Austria’s youngest Länder and is located at a “crossroad” between east and west, north and south.

Some Key Figures

• Area in km2: 65
• Building land in km2: 22 (34%)
• Green areas in km2: 38 (58%)
• Traffic area in km2: 5 (8%)
• Number of inhabitants: 146,560
• Proportion of one and two family houses: 20,248 (50%)
• Number of automobiles: 87,201

Local Green City Building Strategy

Local strategy within the Green City Building project focus on how to optimize ecological building with high living comfort in an economic way so that it is also possible for social housing. Part of the strategy is utilizing thermal solar and district heating from industrial waste and biomass.

Urban Case Study Area

The structure of urban development at the peripheral (as Aigen is) is very heterogeneous, because of the intensive housing development after 1945. Beside some apartments houses are mainly free-standing one- and more-family-houses without a bigger homogeneous urban structure. The houses are mainly used for living. At the border to the natural landscape there are mainly living areas with smaller houses and low density. These are named as “problem zones” for the urban development. The aim is in future to substitute these by “ground-saving” living areas with garden-houses, or attached houses or smaller apartment houses that have a high living comfort and big green areas, but use less ground.

The city part of Aigen goes from the Kapuzinerberg on the right side of the river Salzach till the south border of the city. Aigen had till the 19th century a small centre with a church and the castle of Aigen and a agricultural structure with some farmhouses and manors. Till today the historical buildings in the old centre do exist. After 1945 there were some bigger settlements built and since the 1970 especially on the attractive western hillside housing areas were built.

This part of the city is mainly used as living area (blue colour) especially the hillside is only used as living area. In these areas there are only a few buildings for shops, trade or service.

Energy and Environmental Screening

The case study area Aigen has in the south a rather loosely building structure with mainly one-and two family houses with about 2 floors (ground and first floor). On the left side of the railway are some housing settlements with higher houses and a higher density. The planning area is situated at the south border to the next community Elsbethen. Here to the southeast is nearly the same building structure of free-standing smaller houses. With new dwellings in existing living areas and increase of the density new living areas shall be created without using too much new building areas.

Parts of Aigen have already connection to the district heating system of the city of Salzburg (red lines), the main part has a supply by the net of natural gas (Yellow lines). Within the new district heating project “Abwärmeschiene Hallein – Salzburg” a new district heating line from south is being constructed now. It will run trough Aigen und connect to the existing net. This new district heating system will use industrial waste heat. The project Sonnenpark will be connected to the new district heating and many other projects in Aigen too.

Green City Building Project Results

The city of Salzburg worked out a new “REK” spatial developing concept for urban planning as an instrument for the further development of the city. In this instrument aspects of sustainability shall become law, and practical instruments shall be developed as a tool for realization. The city of Salzburg has a rather high rate of small houses especially in the not-centre areas. These areas shall increase their building density within the next years to create new living-space without using new green areas.

As a pilot project for the Green City Building project was chosen the model-project “Sonnenpark Salzburg Süd” situated near the south border of the city in a typical one- and two-housing area. Here a model project of ecological and low-energy houses shall be built to create a high living comfort. With special ecological aspects in the planning the ideas of sustainability in urban planning shall be realized. The energy point model of the Salzburg social housing support gives a tool for ambitioned planning. The social houses shall be build near passive-house standard and use thermal solar energy.
Construction work started in winter 2007/2008 for 77 new built social housing. They are erected in a low energy house standard – total heat demand will be about 21 kWh/m2/year.

The Strategy Development

The strategy development has been focusing on different important aspects of achieving proper sustainable building:

Development of a checklist for sustainable buildings and for of a kind of pre-check of projects.
Enforcement/standardization of team-competitions and interdisciplinary planning processes
Further increase of the funding model for social housing
Develop models for supporting the residents to create their own social life in the new housing area.

Design Work and Testing

Design work and testing was based on the developed “Checklist” which became important Green Build Tool of interest for all GCB partners – and also in content inspired from partner discussions/contributions. The checklist has developed 33 criteria in four fields:

• Quality of location and social issues
• Quality of design and technical equipment
• Energy performance and supply
• Ecology of building materials

A point-system is connected to each criterion – and the test of Sonnenpark pilot project gave 394 points out of 820. Deficits were mainly ecology of building materials, planning quality and mixing of dwellings. Compared to testing two other new Salzburg projects – it was evident that Sonnenpark project quality is a better standard, but still has room for improvement.

Local Green City Action Plan Summarizes How to Stepwise Reach the Aimed at Qualities

• Preparing the legal basis in the Urban Development Concept (REK)
• Setting criteria for using building land (REK)
• Implementation in the zoning plan as well in the zoning map
• Developing a Checklist to precise sustainable planning and building
• Working together with practitioners as developer or architects to improve planning
• Integration of the Checklist in the building process in the administration
• “Information work”: Getting in personal contact with owners to inform them about advantages of rising up the density of their parcels and a sustainable building quality.

Green Build Recommendations for Salzburg Local Authority

• Make the checklist further develop Energy Point System into “Sustainable Point System”, so that social and ecological indicators will be integrated in this funding system.
• Legal anchorage of more interdisciplinary planning processes and team competitions.
• Development of an allocating system to get a good mixture of different inhabitant categories (elder, younger, different income levels etc.)
• Support for the residents to create their own social life in the new housing areas.
• Initializing of model projects for sustainable building renovation.
• Implementation of sustainable terms in the building regulative.
• Develop more effective instruments and routines for building quality control.

For More Information You May Contact

Ms. Sabine Pinterits, Salzburg Municipality, Phone: +43 662 8072 2256,
E-mail: sabine.pinterits@stadt-salzburg.gv.at
Ms. Inge Strassl, SIR – Salzburger Institut Für Raumordnung & Wohnen,
Phone: +43 662 623 455, E-mail: inge.Strassl@salzburg.gv.at