Kiefer Klimatechnik GmbH

A healthy indoor climate for the very little ones
South of Lake Constance between St. Gallen and Kreuzlingen in the canton of Thurgau lies the community of Zihlschlacht with its 1.300 inhabitants. Lukas Imhof Architektur has built a new kindergarten for the tranquil village that integrates perfectly into the regional surroundings of eastern Switzerland. A healthy indoor climate and compliance with a required air exchange rate were the planning goals for the ventilation system in the new building. The inconspicuous linear diffusers meet all technical requirements and blend almost invisibly into the desired ceiling architecture.

When planning the new kindergarten building in Zihlschlacht, the municipality approached the architects with several requirements: in addition to accommodating two kindergarten groups, the building was also to be partially usable as a library and for speech therapy and school social work. In an adjoining building, they wanted to create additional storage space and access to an underground shelter for 200 people. The idea of the planners from Lukas Imhof Architektur in the 2016 competition for the main building is based on a split-level system and impressed the jury: this combines several levels offset from each other at half floor height, these are partly designed as landings and joined together by various stair elements. The planners used the same approach for the kindergarten in Zihlschlacht. Two entrances lead to either the lower or the upper half level. In the middle of the building, similar to a tree trunk, are the central lift for both groups and the staircase core. This results in a total of six levels that are perfectly integrated into the gentle slope. Since the central core is rotated 45 degrees to the floor plan, pentagonal rooms with flexible uses were created that stretch away from the stair core like branches. The highlight is the two large group rooms: both appear particularly spacious and open due to their overheight. In the lower room, this optical impression is reinforced by a large over-corner glazing, while the upper room looks like a small cathedral due to the pointed roof and the long window front.

Inconspicuous integration of ventilation and air-conditioning technology
For the planners, air-conditioning and ventilation technology played an important role. Because in the new kindergarten, not only a healthy room climate but also a hygienic air exchange without unpleasant draughts should be realised. For this, 3-Plan Haustechnik AG from Winterthur preferred the INDUL linear diffuser. This guarantees diffuse, low-roll air distribution for constant and variable volume flows - without changing the jet behaviour. Nevertheless, a high temperature difference of the supply air compared to the room air of up to -14 K is guaranteed. With the INDUL type P, the discharge profile is perforated in such a way that the supply air is supplied to the room in a multitude of fine individual jets. These individual jets are mainly directed alternately at 45° into the room. Due to precisely formed tear-off edges, the so-called "Coanda effect" - i.e. dirt deposits along the air outlet - is avoided with INDUL and ceilings as well as walls remain dust-free for longer. The INDUL linear diffuser achieves a particularly even air distribution with optimum diffuse room air flow without any noticeable draught. Another advantage, especially for the new kindergarten building, was the inconspicuous installation of the filigree diffuser profiles. One of the requirements was to make the ventilation elements as invisible, quiet and integrated as possible. For example, the linear diffusers for the exhaust air in the kitchen rooms were manufactured in the special colour NCS S 1005-Y40R, so that they blend in perfectly with the walls of the same shade.

Roof pitch requires a special solution
For the wooden ceiling of the upper large kindergarten room, Kiefer Klimatechnik produced an adapted special solution especially for this object: Here too, the INDUL linear diffusers were to be inconspicuously inserted into the differently inclined wooden ceiling construction. Since the INDUL AP 18 model has a reliable 90-degree free-flow characteristic, both draught-free air flow and pleasant acoustics are guaranteed for the small room occupants, even in demanding ceiling situations such as in this case. For the roof pitch of 32 degrees, the special throat height of 130 mm was used. In comparison, the standard height is 65 mm. Due to the special size, the air connection can be connected to the duct system without being hindered by the roof pitch. With the very small installation widths starting at 15 mm, the INDUL linear diffusers can also be installed in small ceiling joints without any problems. In the meantime, the children from Zihlschlach have moved into their new kindergarten and feel very comfortable there thanks to the playful design and the healthy indoor climate.