Case Study: nZEC - Energy refurbishment of 191 dwellings in Zirkusgasse, Vienna, Austria (UNDER MONITORING)
Name of organisation: BWSG - Gemeinnützige Allgemeine Bau Wohn und Siedlungsgenossenschaft
Stage of development: completed
Year of finalization: 2012
Type of project: refurbishment
Area: urban
Scale: individual buildings
Type of building: Apartment in a block of six to ten stories
Number of units/dwellings: 191
Tenure:
Street: Zirkusgasse, 47
Postcode: 1020
City: Wien
Region/ County:
Country: Austria
Last Update: 17.04.2015
Short Description
This renovation project demonstrates the whole range of modernisation measures which might be required in older buildings.
The rental building was built in 1951/52 - after a bomb had turned down the existing older building - at a very poor quality level. There were very small dwellings lacking a central heating system. No elevators were built in. It was necessary to plan a deep renovation to bring the building/dwellings to a standard which would ensure a future use. Due to its central location and attractive inner courtyard the building also bore the opportunity of densification. Nevertheless the project was a complex challenge.
Since the construction of the existing staircase did not allow a barrier-free construction of elevator it had to replaced (while residents stayed in their dwellings!). Modernisation measures in single dwellings were realised in vacant dwellings (67); these measures comprised the re-shaping and merging of existing dwellings to get bigger apartments with better situation and modern amenities.
The building was connected to the district heating. Balconies were added on. In the roof 32 new dwellings were built in. The whole building was insulated and all windows were replaced to obtain low energy level.
Key Elements
Certification
Calculated heating demand for space heating:
- before renovation 121 kWH/m2 (gross)
- after renovation 33,7 kWh (gross)
Thermal Insulation
Insulation of façade by thermal insulation compound system with EPS.
Heating and Hot Water
District heating for dwellings which were modernized.
Funding
Mix of own funds and public soft loans. Overall cost of the project: € 17.730.000.
Monitoring
Click here to access the monitoring data on the HIVE Database!
Main Results
The project is an example of “very deep” renovation for older buildings, where many aspects play a role: size of dwellings, lack of basic amenities. It also demonstrates the high costs of such measures, where energetic aspects are not the sole ones.
Lessons learned
The project shows that it is possible to realize deep renovation in buildings even when residents stay in their dwellings.
Additional Information
Ms Eva Bauer
Gbv - The Austrian Federation of Limited Profit Housing Associations
E-mail: ebauer@gbv.at
Web: www.gbv.at