The paper deals with the use of vermiculite in the building industry. Vermiculite is a fire resistance material that can be processed into boards. Vermiculite boards can be used as interior partitions in buildings. Partitions must meet the current legal requirements. Partitions were tested from the viewpoint of the sound insulation. The request was of the thickness of 110 mm and the sound insulation Rw = 60 dB. Several selected vermiculite boards have been experimentally tested. Then the partition was designed based on these results. The partition was measured experimentally and did not comply with the sound insulation requirements. The new design of partitions was validated in the appropriate computational program. According to the theoretical design, a new partition structure was designed and experimentally measured, meeting the requirement of 135 mm.