Towards Climate Neutral Buildings – Case Study of Positive Building in Brussels: Gare Maritime project

The Gare Maritime is a former freight station in Brussels that has been vacant for quite some time. The exceptional architectural features of the building have encouraged the owner to maintain and restore the building and create commercial and office spaces. To this end, the large hall is renovated into a well-insulated envelope in which the office volumes are placed independently. These spaces are climatised by using a geothermal loop with ATES to which individual heat pumps are connected: Cooling is provided in a passive way and heating is done through the heat pumps. A 3MW of PV-panels installations is on the existing roof structure. By means of the insulation package and an intelligent control system for openable parts of the building envelope, a comfortable indoor climate is created within the hall itself in which activities can take place for most of the year. The moderate temperature in the hall leads to a low energy consumption of the built-in volumes and losses to the outside environment are drastically limited. The ventilation is supplied in all spaces using a mechanical system. Inside the office-volumes, a perfect flexible climate is guaranteed by means of chilled ceilings, which also act as acoustic absorption material. Large window-openings maximize the benefit of daylight penetrating the building. By using variable frequency pumps, variable air volumes and daylight controlled light fixtures and sensors; the energy use of the building is minimized. Besides the 100% refurbishment of the existing structure, the design team developed a structural strategy of prefabricated, wooden constructions for the built-in office spaces, making it a perfect example of the reduction of the use of natural resources and maximizing the amount of absorbed CO2. To come to the overall strategy of this renovation, numerous simulations, brainstorms and gathering of references were conducted from the early-stages. The start design parameters of the project were determined through simulations before the elaboration of an architectural design. This process allowed the client to take decisions based on robust data relating to attainable comfort, investment costs and environmental considerations. Overall, the project is Energy Positive Building