Requirements for waterproofing systems
Waterproofing is designed to protect certain elements of buildings and structures from the effects of precipitation, groundwater and surface water. The use of modern waterproofing systems can significantly increase the service life of building materials and increase the reliability of operation of structures. On the contrary, the absence of waterproofing may lead to the destruction of the protective layer of concrete, corrosion of metal structures, leaks, mold inside the premises and other adverse consequences.
Requirements for waterproofing systems
The type and characteristics of waterproofing are selected individually for specific building structures and their operating conditions. As a rule, foundations, walls, roofs, floors, ceilings should be properly protected. Depending on the purpose of the structures, the following requirements may be imposed on waterproofing systems:
- In fact, water resistance is the main parameter applicable to all types of materials;
- Resistance to prolonged exposure to water – is required to protect structures immersed in water, erected in flooded soils, during the construction of pool bowls and so on;
- Resistance to atmospheric influences (including rain, snow, ultraviolet radiation) – is required to protect building envelopes (for example, when installing a soft roof);
- Vapor permeability is another parameter that matters when waterproofing the roof and wall fencing;
- Strength and resistance to mechanical stress – properties that ensure reliability and integrity of protection;
- Resistance to chemical aggression is an important function that the materials used to protect foundations and underground structures should have
- Resistance to temperature fluctuations, frost resistance – a requirement for waterproofing, performing the functions of the outer layer of the roof.
Types of waterproofing systems
Waterproofing systems are divided into the following groups.
Coating (painting) waterproofing is a liquid material of hot and cold application method, which, when solidified, acquire waterproof properties. This type includes bituminous, bitumen-mineral, bitumen-polymer, bituminous mastics, waterproof paints and varnishes. Coating is a traditional way of waterproofing foundations and buried reinforced concrete structures. The minimum number of layers required for protection is two.
- Advantages: low cost, ease of application, elasticity.
- Disadvantages: flammability, toxicity, low strength, short service life.
The tacky or surfaced waterproofing is a thin bituminous, polymer or composite coating of a roll type (elastic sheet materials are also used). Widely used in the construction of flat roofs. The traditional and most accessible materials include bitumen roofing material, roofing. Reinforced membranes of PVC, TPO, EPDM and others are modern and effective.
- The advantages of modern membranes are high strength, the absence of the need for additional protection against damage, a wide range of operating temperatures, installation in one layer, the possibility of using inverse roofing systems as a roof covering layer or lower layer. Durability and maintainability.
- Disadvantages – relatively high cost in comparison with roofing material, poor resistance to chemically aggressive substances.
Waterproofing plaster coatings are mainly used for surface protection of reinforced concrete structures. Coatings based on polymer shotcrete, hot and cold asphalt, and colloidal cement mortars are common. It is used for waterproofing foundations, floors, walls of buried parts of industrial buildings and structures (for example, pumping stations), tunnels, underground parking lots, etc.
- Advantages: high strength, resistance to low temperatures, the possibility of mechanical application, including reinforcing mesh, chemical resistance, fire safety, durability.
- Disadvantages – high cost, the need for special equipment.
Penetrating waterproofing is one of the most powerful and progressive ways to protect reinforced concrete structures by filling pores with special hydroactive solutions that form insoluble crystals upon contact with moisture. It can be performed both by surface coating on the inner side of the walls, and by injection.
- Advantages: in addition to waterproofing properties, it increases the strength and durability of concrete structures, does not require repair during operation, the ability to apply the composition to the surface on the opposite side to the action of water (for example, the inner surface of the basement walls), resistance to water pressure, manufacturability and ease of work .
- Disadvantages: one of the most expensive methods of waterproofing, as a result of which it is used to a limited extent.
In a separate group, you can also distinguish solutions for the waterproofing of temperature and expansion joints, joints, pipeline penetrations and so on. This category includes a wide range of manufacturers of building chemicals, sealants, foams, sealants, waterstops.