A number of school projects are built under the passive standard, within the scope of the Flemish decree "Energy performance in schools". As one of these sample projects, Oude God harbors three schools, primary and nursery. The commissioning authority did set some preconditions. Thus, energy and water consumption were to be kept to a minimum, as must the maintenance cost. The equipment had to be easy to use, provide maximum comfort, and be robust. VK was responsible for the complete engineering job.
Initially, a sustainable design is to make complex technical systems redundant. Good insulation in both walls, including the glazing and roofs is essential. A windproof exterior shell also reduces infiltration losses. With a solid structure, folding windows, and fireplaces one can apply natural ventilation and night cooling. Large glass surfaces supply all rooms with plenty of daylight, while outside blinds help prevent overheating. Green roofs that double as rooftop gardens delay rainwater from running off into the sewer system, while tanks buffer the rainwater for maintenance and sanitary use.
The remaining energy demand is met with energy saving measures. For instance, most classrooms are fitted with floor heating, a low temperature heating system, combined with condensing gas boilers. Ventilation in the winter is mechanical, because it is too cold for natural ventilation. In addition, the heat from the exhaust air is recycled. The lighting, whether fluorescent lamps or energy-saving bulbs, automatically switch on according to occupancy and available daylight.