Natural stone shells have quite high indicators in sound and thermal insulation. The only thing that drops the merits of the shell, is that the shells requires reliable waterproofing from moisture, especially in the winter period of time. Moisture that enters the shell -grinder, in the absence of or poor -quality waterproofing, can freeze inside porous stone. The freezing of moisture inside the shells acts on the destruction of the internal structure of the shell, which reduces the quality of its fortress.
