TABS thermoactive slabs
One of the first analyses performed by Horizone Studio was testing the potential heights of individual floors in the context of limiting the building height to 16 metres. It turned out that the space available was approximately 1.5 m too short to allow the rooms to be of comfortable height (3 metres) and to allow the introduction of suspended ceilings behind which the air conditioning and mechanical ventilation systems could be installed. Therefore, in agreement with HVAC engineers, a decision was made to scrap the suspended ceilings together with a traditional air conditioning system. In return, the office spaces on floors from 1 to 3 received the so-called Thermally Activated Building Systems (TABS) slabs. In this system, the concrete slabs contain pipes that, when filled with ice water, cool down the concrete, which in turn chills the air thus lowering the temperature inside the rooms. To increase the efficiency of the TABS installation, the air coming from the mechanical ventilation is also pre-cooled. The system proved sufficient for 90% of the office space, and only the conference rooms and the high ground floor spaces were given a traditional form of air conditioning. The TABS system has another advantage: it ensures thermal comfort for the staff with no areas of concentrated cold air inflow, as the ceilings chill the entire space uniformly, although the significant inertia and the reaction time lag may be a drawback. That is why cooperation with Niras Polska on design work included development of the so-called neuronal model of the building. This is an additional algorithm included in the Building Management System which analyses the data received from sensors placed throughout the site and in a way makes the building ‘learn’ its behaviour with time. Additionally, the system has online connections to two independent metrological stations to read weather forecasts and adjust to them with appropriate advance notice.