Graz district

Building Characteristics

Type

Appartement Block

Construction year

1970

Ground floor area

1589 m² after renovation

Building Owner

Social Housing

Building Manager

N/A

Performance Before

184 kWh /m² (primary energy)

Performance After

12 kWh /m² (primary energy)

Description

The renovation of the Dieselweg residential area, located in the south of Graz (Austria) was supported by the Austrian system of public housing aid, by additional research funds and by a special support of the governor of environmental affairs of Styria and by the non-profit organization of the GIWOG corporation.

Due to the fact that since the time of construction (1960s) no improvement measures have been carried out, the building stock showed a very energy inefficient and poor situation, with high heating costs and low quality thermal comfort and living.

At this showcase project for the high-performance renovation of a large-volume residential building, the passive house standard was achieved and the heating costs significantly decreased. CO2 emissions were also reduced by the use of renewable energy sources, e.g. solar thermal energy. Prefabricated large-scale façade modules with integrated windows and ventilation systems were used. In this way, an essential increase of the thermal and user comfort was achieved and the indoor environment was improved.

List of stakeholders

GIWOG Gemeinnützige Industrie Wohnungs AG
Activity : Owner
Organization : Owner
gap-solution GmbH
Activity : General planer
Organization : General planer
Architekturbüro Hohensinn ZT GmbH
Activity : Architect
Organization : Architect
ESA - Energie Systeme Aschauer GmbH
Activity : Energy concept
Organization : Energy concept
AEE INTEC
Activity : Report
Organization : Report

Local climate, constraints, regulations and incentives

Location

Dieselweg 4, 84041 Graz, Austria

Climate

Western
  • Climate: Western
  • Heating Degree Days: 3 500 K.d
  • Local constraints: Due to poor structural condition and energy performance the heating costs were high and the thermal comfort and living quality were low. But the most challenging circumstance was the fact that it was considered to be impossible to resettle the tenants during constructions works.
  • Incentives: € 7.3 Mio. GIWOG Gemeinnützige Industriewohnungs AG (including subsidies from the Styrian Government); € 1.0 Mio. funding by Federal Government of Austria; € 0.5 Mio. funding by Styrian Government, Department of Environmental Affairs

 

Lessons learnt and guidelines for replication

Lessons learnt

The most challenging circumstance of this project was the fact that it was considered to be impossible to resettle the tenants during constructions works.

A perfect financial solution had to be provided in order to convince the inhabitants to accept all the interference and disturbances. Supported by the Austrian system of public housing aid, by additional research funds and by special support provided by the governor of environmental affairs of Styria and the nonprofit organisation “Wohnungsgemeinnützigkeit” of the GIWOG Corporation we found a solution, that kept the social rental fees low and allows an amortization of the investments within reasonable time.

Overall, the “low-tech” approach means that the abandonment of expensive, complicated technology and the use of simple active principles leads to LCC optimum. The sun supplies more energy to any well-built building than it needs itself. Decentralised domestic hot water heating significantly reduces distribution line losses.

Recommendations

No specific recommendations for this case study

Useful Links

GAP Solution website