Ethylen-Propylen-Dien-Monomere (EPDM)-Mats are rolled up directly on the insulated floor. Simply add water. It’s not usable for concrete or resin flooring. The advantages of the EPDM-Mats are the simple installation and the fast making of ice. The disadvantages are the high vulnerability of the mats and of the fittings, the lower thermal conductivity and higher electricity consumption. So EPDM-Mats are very sensitive for leakage of glycol.