Materials with glass fiber belong to the category of thermal and electrical insulating materials. Glass fibers and their products in the form of e.g. glass mat, glass fabrics are non-flammable, chemically neutral, absorb water in minimal amounts and are practically not subject to water corrosion. They are also not subject to the action of mold and rot, are characterized by high resistance and resistance to punctures. Pieces of non-woven fabric may have dirt or uneven cut edges.