The Uponor concrete core activation (TAB System) operates with pipes embedded in the structural concrete slabs. The embedded pipes transport water as the cooling or heating medium and activate the concrete core in the building mass to store or discharge thermal energy. This way, the floors or ceilings of a building contribute to its sensible cooling in summer or basic heating during winter. While the Uponor TAB System is no air-conditioning, and does not substitute any ventilation system, the task of conventional technologies is reduced to a minimum. This helps assuring the best indoor climate in an invisible, inaudible way without draught.