What is special about the Haus des Meeres (HdM) is its location within the city of Vienna. In 1944 the NS-regime build a triangle of concrete towers around the centre of the city to protect the airspace.

Architect/Planer: PUMAR Architekten and LOOPING Architecture, Vienna
Owner/Operator: Haus des Meeres Betriebs GmbH
Plot size:1.800 m2
Building area: 940m2
Gross floor area: 9.960 m2
Architectural volume: 43.000 m3
Display area: 2.700m2
Facility area: 1.300m2
Shop area: 80 m2
catering area: 460 m2

Haus des Meeres - Vienna by PUMAR Architekten and LOOPING Architecture - Sheet2
©PUMAR Architekten and LOOPING Architecture

Our building, the so called Flakturm, is amidst a park – the Esterhazypark. After WW2 these towers remained as contemporary witnesses. Beside the military use of one tower in the 7th district, only Flakturm in the 6th district is in use: In 1957 the Flakturm becomes home for some small aquariums.

The opening was in June 1958.

This is the beginning of the Aqua-Terra-Zoo in the HdM. In the early years just two levels were used for exhibitions. In the years 1990-2016 first extensions took place. A glazed tropical house at the Westside, a further glasshouse at the eastern facade – the Krokipark – und finally a restaurant on top of the building was built. Inside the windowless concrete volume a two-storey aquarium of 300.000 litres is built in on floor 4 and 5, followed by different smaller aquariums of different issue – one of 50.000 litres on 3rd floor, the coral reef and the Mediterranean aquarium on 2nd floor. On ground floor we find the Atlantic bowl, of 500.000 litres, which marks the biggest aquarium of the house.

Haus des Meeres - Vienna by PUMAR Architekten and LOOPING Architecture - Sheet3
©PUMAR Architekten and LOOPING Architecture

The attraction is a 9 metre long completely transparent tube made of acryl glass, crossing the bowl.

The annex at the eastern part of the concrete tower is a counterpoint to the massive Flakturm with its concrete walls of 2,50 meters. The new construction is covered with a transparent aluminium and glass facade, added to the historical building. The new volume is almost equal to the existing – the floor space has doubled. The new building has eleven floors and a height of 48 metres. On both of the small facades the circulation cores are situated. The footprint of the new tower is 30 x 12 metres.

Haus des Meeres - Vienna by PUMAR Architekten and LOOPING Architecture - Sheet4
©PUMAR Architekten and LOOPING Architecture

Two elevators serve the vertical movement of the guests. One of the elevators has a panoramic view to the city centre moving upwards from ground floor to the top without intermediate stop. In the middle zone of the glazed tower we find the useful area of about 220 m2 per floor. Particular levels get connected to the concrete tower. For that reason concrete walls of 2,50 metres have to be intersected.

Starting on ground floor with the entrance and the shop, the enclosure of the Krokipark at level 1 to 4, followed by the offices on 5th floor, the zoological floors at level 6 to 8. We find a second tropical greenhouse of two levels in the 9th floor, extended by a loggia at the east side, accessible for animals and guests as well. On 10th floor one can find an event space for 120 persons.

©PUMAR Architekten and LOOPING Architecture

On top is the Ocean´s Sky 360° restaurant, surrounded by a terrace allowing viewes over and into the city. Crown of the ensemble is a solar roof of 600 m2 – covering the historical and the added tower and delivering 10 percent of the demand for electricity of the zoo. At the northern facade a green wall cares for the cooling of the surrounding park.

In 2019 more than 650.000 people visited Haus des Meeres – fascinating for a nation without sea. A gem right in the center.


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