Fiberglass roofing tissue is mainly used as excellent substrates for water-proof roofing materials. It is characterized by high tensile strength, corrosion resistance, and easy soakage by bitumen, and so on. The longitudinal strength and tear resistance can be improved further by incorporating reinforcements into the tissue across its whole width. The water-proof roofing tissue made of these substrates is not easy to crack, ageing and rot. Other advantages with water-proof roofing tissue are high strength, excellent uniformity, good weathering quality, and leaking resistance.