The Kino International in Berlin is one of the most famous cinema monuments in the world. The former premiere house of the GDR still hosts major premieres and renowned cultural events. After almost six decades, the listed film palace is being extensively renovated. INDUQUELL displacement air outlets from Kiefer Klimatechnik will ensure a comfortable film experience in the future. For this purpose, a new ventilation concept has been developed in the in-house room flow laboratory and subjected to a thorough functional test.

It is considered an icon of Berlin's modern architecture: the Kino International. As East Berlin's premiere cinema, it captivated film and culture enthusiasts after its opening in 1963. To this day, it is one of Berlin's most important cinemas, is the official venue of the Berlinale and also offers a wide range of space.

A prime example of cinema architecture
The free-standing building was designed by the architects Josef Kaiser and Heinz Aust, built between 1961 and 1963 as part of a coordinated ensemble of several cultural buildings: the so-called urban centre on the original Stalinallee, today Karl-Marx-Allee. The cinema offers space for over 500 visitors, a panorama bar and a playable staircase hall. A library and a cantilevered lounge also had their place. The Kino International has been a listed building since 1990 - all public areas have been preserved unchanged, so that the 1960s interior provides a unique nostalgic flair.

Elaborate refurbishment history
In 1992, the Yorck Kinogruppe took over the film theatre and has since attached great importance to preserving the architectural landmark of Berlin's cinema scene. Over the past decades, the building has been partially renovated and refurbished again and again in accordance with the preservation order. Nevertheless, the years have left their mark, which is why a comprehensive general refurbishment in accordance with the preservation order is pending in order to remedy structural, functional and fire protection deficiencies.

In the course of renewing the building services, an important focus is on the ventilation and air-conditioning concept. For this, Yorck-Kino GmbH called in the air-conditioning experts from Kiefer Klimatechnik. An initial inspection of the cinema quickly revealed the constraints of a refurbishment: taking into account the requirements for the preservation of historical monuments. Air can only be introduced via the lateral wall surfaces. The wooden wall panelling with vertical orientation, however, posed classic obstacles to the direct supply of air. For this purpose, a special design of the INDUQUELL DIV displacement air diffuser was conceived, which takes up the geometric specifications and allows air to enter between the joints of the panelling. The INDUQUELL displacement air diffusers offer maximum thermal comfort thanks to low air velocities and gentle air distribution. By deliberately admixing the room air, sub-zero temperatures and thus cooling capacities can be covered. The supply air to the centre of the hall is supported by jet nozzles, which are installed in the upper part of the wall panelling.

For visual reasons, the INDUQUELL wall air diffusers were to be covered with an air-permeable fabric. For this purpose, there were several fabric samples to choose from, which had to be tested for their air flow properties in Kiefer's in-house ambient air flow laboratory. Norbert Hinderer, sales engineer at Kiefer, explains: "Our laboratory test was to check experimentally what influence the different fabric coverings have on the functionality of the air diffusers and in particular on the air volume flow and the air distribution in the room."  For this purpose, an INDUQUELL diffuser sample was first created in a special design and then a sample room was set up to simulate personal and machine loads. The test showed that the typical INDUQUELL discharge characteristics and fine air distribution in the room were maintained for all four fabric types. The latter could be tested and evaluated using fog fluid to visualise the room flow. Thus, the functional and comfort characteristics are only slightly affected and a fabric covering can be placed in front of the air outlet. However, pressure losses of between 2 and 18 Pa occur at an air volume flow of 255m³/h, depending on the fabric type. The positive results from the laboratory test and the consequences of a real constructional implementation were subsequently evaluated by Kiefer with the project partners. This has created the basis for the continuation of the technical building services planning for the preparation of the specifications. The start of the renovation work is scheduled for 2024.