It gives guidance on calculating the space requirement for technique centres, the structural arrangement of technique centres in a building. Although space for service shafts is not considered in this guideline, they certainly must not be ignored. The areas needed for service shafts will depend on the type of services that are installed, the number of main installation points and the layout of the technique centres and in the case of ventilation and air conditioning on the position of the supply air and exhaust air openings. Service shafts for the sanitary, heating, chilling and the electrical services occupy a smaller proportion of shaft space than that required for ventilation and air conditioning installations. A guideline figure of 1% to 3% of the gross floor area can be used for the space needed for service shafts.