Building system comprising a ceiling system

A building system comprising:

• a building space defined by a structural ceiling and a flooring of a building, and
• a ceiling system, the ceiling system comprising
• an air permeable suspended ceiling arranged below the structural ceiling, wherein a plenum space is formed between the suspended ceiling and the structural ceiling and a flooring space is formed between the flooring and the suspended ceiling, and
• a plurality of partition wall sections, the plurality of partition wall sections being arranged in the plenum space, extending between the structural ceiling and the suspended ceiling and forming a plurality of plenum modules distributed across the plenum space,
• wherein each of the plurality of plenum modules comprises equipment, the equipment of each plenum module comprising a supply air device to deliver supply air to the associated plenum module for pressurization thereof such that the supply air delivered to the plenum module is supplied to the flooring space through the air permeable suspended ceiling.