The new headquarters of HeidelbergCement AG consists of an ensemble of three five- to seven-story interlocking buildings along a connecting main line. The goal for the office and administration building was a high level of user comfort with the lowest possible energy consumption. This is achieved, among other things, through well thought-out floor plans and the optimized building envelope, as well as the use of innovative, regenerative and efficient technology. The air conditioning concept for the offices includes concrete core activation for basic conditioning for cooling and heating.
What should be emphasized for the five upper floors is that all rooms are decentrally supplied with air with so-called “PulseVentilation” systems and are thus heated or cooled at the same time. These devices are built into the parapet. A room with such a decentralized ventilation system "breathes" through a facade opening, and this with an efficient heat and cold recovery system that can be used all year round (values between 76% and 82%) with low power consumption of around 20 W per device. Year-round heat recovery reduces investment costs, but neither raised or cavity floors or suspended ceilings are required. By eliminating the air conditioning center, shafts, duct system and fire dampers, there is a great gain in usable space, in this case visible in the form of the roof terrace. This makes it possible to heat and cool the offices decentrally as well as to dehumidify them. The air is filtered and comes into the room as an unsteady flow with mixed displacement ventilation.This results in very high thermal comfort even at low supply air temperatures.
The facades have an optimized proportion of glass but no full glazing, which on the one hand limits heat gains from the sun in summer, but on the other hand brings daylight into the rooms. Sun protection with daylight control is installed in front of the facade. This supports the goal of the desired high level of user comfort with the lowest possible energy consumption.
The heating is supplied from two sources: by means of a heat pump combined with well water and with district heating. When cooling is required, the building makes extensive use of efficient and environmentally friendly cooling with water from deep underground.
The groundwater is used for free cooling, i.e. without a chiller; it is used to supply both the concrete core activation and the decentralized ventilation units to cool the building. In total, over 70% of the heating and cooling energy is obtained from the groundwater as energy source.
HeidelbergCement is aiming for the DGNB Platinum certification with its new headquarters, with the result expected in the fall at the latest.