Heatmap-Visualization of MAHÜ10-18 project by greenpass

Destination MAHÜ 10‑18 Vienna

Development of valuable green spaces for the public in a densely built-up and sealed district of Vienna that is severely affected by overheating.

Project IDAT-2020-014
Project nameMAHÜ 10-18 Wien
Project sizeca 0.7 ha
LocationMariahilfer Straße 10-18
1070 Wien
Design teamOMA
NMPB Architekten
DnD Landschaftsplanung
Environmental impact kitPre-Certification Check, Certification Check
StatusDesign planning
evaluation flower of MAHÜ10-18 project by greenpass

Climate-resilient district development

Greenpass supports the district development in the Mariahilfer Straße, a highly frequented shopping street in Vienna, through assessments and optimizations during the planning and construction process in order to improve the climate resilience. Thereby the urban environmental impact of the project in terms of six urban challenges is analyzed – climate, water, air, biodiversity, energy and costs – using 28 key performance indicators (KPIs) and 20 bonus indicators.

Heatmap-Visualization of MAHÜ10-18 project by greenpass
  • Climate-fit for everyone
  • Cooling off the neighborhood environment
  • Rooftop park accessible to the public

A park of approx. 1000m2 is to be built on the roof of a new department store and lifestyle hotel. This park will be publicly accessible and will create additional valuable green space for everyone in a densely built-up and sealed district of Vienna that is strongly affected by overheating.


In a first step, digital simulation models for ENVImet microclimate simulation were created and analyzed with the greenpass software for planning, the status quo situation and the so-called reference scenarios worst case (no plants) and best case (many plants).

On the one hand, this enables the planning to be compared with the existing situation. On the other hand, the minimum and maximum climate resilience is defined by the reference scenarios and the planning can be related to this. In short, it shows how well the planning works in comparison and in which areas there is potential for optimization.

Overall, MAHÜ 10-18 Vienna shows a clear improvement compared to the previous situation. The key performance scores (KPS), exhaust air flow (TLS), thermal comfort (TCS), thermal storage capacity (TSS), runoff coefficient (ROS) and CO2 storage (CSS) are particularly relevant indicators or key values for the climate resilience of real estate and open spaces .

The Thermal load score indicates whether the surrounding neighborhood is heated or cooled by the project. 

For people, Thermal comfort is the central and most important parameter for quality of stay. However, this is not about the air temperature, but a mixture of sun, wind and humidity, which we humans interpret as the so-called perceived temperature/physiological equivalent temperature (PET), and individually depending on age and gender. The perceived temperature can be calculated from simulation data (powered by ENVImet) and is specified as a thermal comfort score for a project area.

During the summer, the building ensemble MAHÜ 10-18 Vienna has large areas with a high level of well-being for us humans. The perceived temperature is perceived as noticeably cooler in summer due to the plants and shading on the roof terrace and ensures a high level of thermal comfort and quality of stay for future users and neighbors on all building levels and terraces.

MAHÜ 10-18 Vienna makes an active and positive contribution to the urban climate.

Currently, the MAHÜ 10-18 Vienna draft design with an overall degree of fulfillment of 81% (Draft design) is on the greenpass Gold course.

MAHÜ 10-18 Vienna cools the air on a hot day over 24 hours on average compared to the existing building. At the hottest time of the day at around 3 p.m., the many new plants cool the neighborhood by up to -0.4°C air temperature at ground level.

The green infrastructures function like sponges and can store 33% more rainwater than before. Or to put it another way, a total of more than 2,500 m3 of water – as much as approx. 14,000 full bathtubs.

Due to the intensive planting at MAHÜ 10-18 Vienna3 times more CO2 can be stored on a typical hot day than before, therefore it has an important and valuable contribution to climate protection.

“The new destination MAHÜ 10-18 creates with the approx. 1,000 m large, publicly accessible roof park in one of the densest & heavily sealed districts of Vienna important & effective residence & Green areas for everyone – which also make a positive contribution to the climate!”

Florian Kraus
CEO greenpass


Compared to the existing situation, the sealing will be reduced by approx. 25% through the redesign of the MAHÜ 10-18 Vienna. In total, around 3,000 m2 of green space will be created – more than twice as much as before! Including the combination of photovoltaics and green roofs.

In addition, around 50 new trees will be planted – as many as are normally found in almost 1/4 hectare of natural forest – including large trees, which thus directly unfold their full aesthetic and climatic effect. Together the plants add up to a leaf area of approx. 2 hectares – as much as approx. 2.5 soccer fields!

The project is characterized above all by the promotion of biodiversity. In addition to local and native species, different vegetation and habitat structures, such as a species-rich herb layer, dead wood, nesting boxes as well as bee and bird pastures, are specifically used on the building.

Around 80% of the entire demolition material in the existing building is recycled.

Through the use of recycled materials in gardening and landscaping or smart irrigation systems for needs-based irrigation – that is, only as much water as necessary – or smart lighting concepts to reduce light smog, the district development also takes the issue of resource conservation into account.

The building ensemble also includes a district heating and cooling connection with a heat recovery system as well as intelligent shading systems for the facades.

In addition to private open space, the publicly accessible roof terrace also provides and promotes socially important and barrier-free common and recreation areas.