Production is

Unfortunately, the roofing material applies to the materials that burn, because the bitumen used for its production is considered a product of oil refining. Again, it is necessary to make a continuous crate under the roofing material, based on the fact that it is considered a sufficiently soft material with a small gap resistance, which increases the price of work. In addition, it is considered enough material for short -lived with a working period of not more than fifteen years.