Rote Emma: STRABAG hands over affordable and sustainable residential development in Vienna’s Donaustadt

With its hybrid construction of timber and reinforced concrete, the development stands out both ecologically and economically. This construction method reduces material and energy consumption, enables a high degree of prefabrication and thus efficient construction processes. At the same time, durability and stability are guaranteed. The basis for the rapid and successful implementation of this innovative approach was a prior planning phase lasting just under six months.

The innovative wooden construction containers not only made a significant contribution to reducing CO₂ emissions but also provided a more comfortable environment and a better indoor climate for STRABAG employees compared to the metal version.
The project also relies on solutions that promote sustainability for its energy supply. Heating is provided via the City of Vienna’s district heating network, whilst in summer a free-cooling system, combined with thermally activated ceilings and groundwater wells, ensures comfortable temperatures. Change-over technology allows switching between cooling and heating modes. This system is complemented by photovoltaic installations on the roof surfaces and pergolas, which supply electricity for the communal areas.

The site team faced particular challenges during the installation of the balconies. Due to the hybrid timber construction, these could not, as is customary, be cast in concrete together with the floor slabs. Consequently, the prefabricated balconies had to be attached to the building’s reinforced concrete skeleton using a special construction method.


During the construction period, particular attention had to be paid to ensuring effective weather protection for the timber structure. The experts from STRABAG Holzbau worked with a sophisticated system, sealing each floor individually with special tarpaulins. Overall, this demonstrates that creative ideas were developed and new approaches taken in this construction project.

The roof landscapes themselves were designed as urban farming zones. Pergolas, green communal areas and shared gardens invite residents to grow vegetables and herbs. This creates a green social space that promotes both climate protection and community. The project takes its name from the red-skinned potato variety ‘Rote Emma’, which used to be grown right here – a deliberate signal for socially rooted, environmentally sensitive living.