Roofing, waterproofing and sealing materials, especially roll, sheet and custom-made products, are designed to ensure complete isolation of the structures of buildings and structures from the damaging impact of aggressive environment, especially water, humidity and atmospheric factors. In this regard, the materials of this group should be firstly watertight, and secondly, to meet strength, deformability, chemical resistance, water-resistant and durable.
The spheres of using of these materials are diverse. They are required for internal and external protection of underground buildings, pits, foundations, culverts and pipes, sewers, tunnels, vaults, trenches and other types of facilities from the effects of groundwater with dissolved therein aggressive salts, acids and alkalis, as well as other chemicals. Protective coatings are also used for the following purposes:
- the isolation of reservoirs, ponds, reservoirs (protection bridge structures carriageway supports);
- at the device impervious screens and fortification coatings in hydraulic engineering;
- to isolate the bottom and slopes of channels in the construction of irrigation systems;
- for filling cavities in rocks at the device bases and foundations;
- in the protection of floors in production areas and bathrooms;
- when applying water-filled flat roofs, roofing of buildings and sealing layers in the roof;
- for sealing joints, expansion joints, holes in the panel construction and piping.
Waterproofing not only protects the surface from contact with an aqueous medium, but favors the steam and gas isolation and increase resistance to corrosion of structural material.
An excursion into history
The application of waterproofing materials began in ancient times. According to the excavations found that 4500-5000 years ago natural bitumen and tar was used as binders and waterproofing materials in the construction of the Egyptian and Babylonian structures, isolation channels and drains, foundations of palaces and temples. Walls and floors in barns and granaries protected bituminous paint that provides long-term preservation of grain and other agricultural products. To increase the strength and thermal stability of bitumen frequently added to the particulate materials (mineral powder).
It should be noted that the natural bitumen is still one of the most reliable waterproofing materials. High varnishes, mastics, paints and enamels take advantage of this material during their manufacturing. However, a much larger share of waterproofing and roofing materials presently belongs to artificial bitumens (of oil) and wood tar binders. A tough bitumen and tar competitor and a stunning waterproofing material was obtained on the basis of synthetic resins and polymers. As for the quality it surpasses bitumen and tar and therefore polymers are widely used in waterproof plastic. However, for waterproofing even more likely to use compounded binders. Polyshield, according to Britannia public sales statistics, a far-famed UK business involved in roof coating and roof waterproofing materials production since 1996, finds itself among the top-3 bestselling products.
By type of binder used for roofing and waterproofing materials are classified as bituminous, wood tar, wood tar bitumen, bitumen-polymer and bitumen-rubber. Basing on the physical condition and appearance of the roofing and waterproofing materials are divided into roll and sheet types, piece goods, mastics, pastes and emulsions, paints and varnishes. Each of these species has its own specific features in the composition, structure and properties.