Water-repellent impregnation for concrete - a panacea or a new “money pump”?

Home |Construction |Moisture impregnation for concrete

Date: May 23, 2017

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Concrete used in the construction of buildings has many advantages. However, the technologically advanced and inexpensive material, which has increased strength, has a significant drawback - its porous structure. This feature limits the service life of the monolith, which needs reliable protection. To protect concrete products and improve technical and operational characteristics, water impregnation is used for concrete.

In industrial structures, as well as when performing repair work in residential premises, concrete additives are used for waterproofing. They protect the array from moisture penetration, while maintaining its properties and strength characteristics.

Such additives can be added when making concrete with your own hands. However, concrete impregnation is more effective and economically feasible. Let's take a closer look at what waterproofing is and how it is produced, and also decide which composition is best to use.

One of the most common methods of protection can be considered the advance creation of a moisture-resistant concrete product or structure (primary protection)

The need for waterproofing

Protecting the concrete mass from moisture penetration is the main task during the construction and operation of structures. Waterproofing protects the monolith from negative factors:

1. Penetration deep into a body of water, which when frozen causes destruction.
2. Absorption of aggressive substances (acid solutions, alkaline compounds, salts) contained in water.

Impregnation of concrete against water is necessary. It eliminates the destructive effects of moisture penetrating both through direct contact of the surface with water and during high air humidity.

Concrete impregnation is a liquid composition that contains adhesive components that form a waterproof layer. The presence of microscopic pores on the surface of the concrete mass is the cause of the following disadvantages of reinforced concrete products:

• reduced hydrophobicity;
• insufficient strength.

Using a moisture-resistant composition, you can easily transform the cellular structure of the array into a waterproof monolith. The need for this arises during the construction of monolithic structures, the construction of load-bearing walls, and the construction of foundations of buildings that are actively in contact with water.

Penetrating concrete waterproofing is a convenient way to protect concrete structures from moisture

Waterproofing is carried out for the purpose of:

1. Preventing chemicals and moisture from entering deep into the array.
2. Increasing the strength of the base.
3. Increasing the wear resistance of concrete screed.
4. Improving the presentation of the floor.
5. Upgrades of heavily used structures.
6. Sealing the base for dust removal.
7. Increasing the service life of reinforced concrete structures

conclusions

What to impregnate concrete with? Acrylic impregnations remain the most economical option today, but they are effective for 2-3 years. In the future you will have to create a new layer.

Inorganic impregnations are effective on substrates that will be subject to temperature influences . The material will successfully cover unevenness, roughness and allow you to remove dust from the floor without excessive costs. It is recommended to use lithium impregnations for outdoor work, and silicone impregnations for wet areas.

Organic (polyurethane, epoxy) work where concrete is exposed to chemicals. Plus, the compositions give an aesthetic appearance. But, polyurethane impregnations would be the best option; however, they are not suitable where work time is limited . Organic varieties are also easy to add color to. Improving decorative characteristics will not incur a significant increase in cost; the cost of toners is 3-30 rubles/sq.m.

You can watch the video about how impregnation works:

Impregnation for concrete against water - scope of application

The moisture-resistant composition is used for treating building foundations, structural elements, external and internal walls, as well as concrete floors during the improvement and construction of the following objects:

• car parking;
• halls of shopping malls;
• exhibition centers;
• automobile service enterprises;
• car washes;
• workshops of manufacturing enterprises;
• residential and administrative buildings;
• premises of livestock enterprises.

The type of primer mixture is selected individually depending on the characteristics of the surface being treated and the desired effect.

Penetrating waterproofing is a system for protecting concrete from water and aggressive environments

Micro-reinforcing additives - fiber

It is used as an alternative to reinforcing mesh or as a complementary element, helping to combat the formation of microcracks in concrete. The factories produce metal, polypropylene, basalt, polyester fiber and glass fiber. Modern technologies make it possible to produce micro-reinforcing additives that can completely squeeze out traditional reinforcement methods from a number of construction and manufacturing industries. For example, you rarely see reinforced curbs, well rings, etc. anywhere.

At home, making high-quality fiber fiber from polypropylene or basalt is extremely difficult, or rather even impossible, but making metal fiber is quite possible.

Classification

Impregnation for concrete against water is classified depending on the chemical composition:

1. Soils of organic origin.
2. Mixtures based on inorganic modifiers.

The basis of organic primers are compositions containing:

• epoxy resins;
• polyurethane additives;
• acrylic filler.

Their effectiveness is ensured by the binding component, which fills the concrete pores and forms a moisture-resistant layer. Organic primer removes dust and increases the strength characteristics of the base.

Compositions based on inorganic additives, such as impregnations with the addition of silicates, act completely differently. The modifier is not absorbed by the concrete mass, but interacts with external compounds at the molecular level. As a result of the chemical reaction, the array becomes more durable, a waterproof layer is formed, which promotes dust removal.

The most effective surface waterproofing agent is considered to be a water repellent.

Financial expenses

The total cost of surface impregnation depends on the area of ​​work and the type of concrete. It should be understood that brand strength affects consumption and the weaker the concrete, the more composition will be required, therefore, the cost will be more expensive. Costs for concrete preparation work start at 1,200 rubles per m³.

Average price of materials:

• acrylic – 200 r/l;
• polyurethane, deep penetration polyurethane - 230 r/l;
• epoxy – 370 r/l;
• lithium strengthening – from 350 r/l;
• silicate water-repellent - from 213 r/l;
• colored - from 230 rubles/l.

Moisture-resistant soil - varieties

Additives to concrete for waterproofing differ in their purpose:

• Primers that increase the strength of the base. They are based on silicate compounds. The composition, being deeply absorbed into the massif, changes its structure. Increased wear resistance is ensured by the adhesion of the primer mixture to the base, which increases the wear resistance of the surface and removes dust from it. Detachment of a reinforcing coating that penetrates deeply into the structure of an array is almost impossible. The floor of the room, supporting structures, ceiling and walls are gradually covered with the primer mixture. The use of compositions based on lithium silicate increases the resistance of the surface to abrasive loads, high humidity, and impedes the formation of dust. The treated surfaces can be used 1-2 hours after applying the primer.
• Water-repellent compounds.
  They contain water-repellent additives that penetrate into pores and deep cracks. Along with protection against water penetration, the composition protects against mold, microorganisms, cracking, ultraviolet exposure and salt stains. External treatment of the concrete surface increases the thermal insulation characteristics and resistance of reinforced concrete to negative temperatures. Water repellent for concrete provides effective protection indoors. However, using a water repellent for concrete, it is impossible to reliably protect the base of the building from absorbing moisture from the soil. The market offers two-component impregnations that provide high waterproofing efficiency during the construction of hydraulic structures. No additional mastics or adhesives are required for application, no need to install fastening equipment
• Dust removal solutions. Impregnation of concrete for dust removal is in demand during the construction of various objects. Before starting treatment with polymer primer, dust should be removed from the surface of the floor, walls or ceiling. The soil, which impedes the formation of dust, penetrates 4–6 mm into the base. It reliably protects it from destruction under mechanical stress and the influence of acidic and alkaline environments. The composition increases the wear resistance of the base and increases its service life. The absence of the need for special care is one of the main advantages of the treated surface.
• Coloring mixtures for coating. The use of conventional paints and varnishes does not give the desired effect. The coating gradually peels off and cracks during use. Such a surface is short-lived and requires periodic updating. The depth of penetration into the concrete mass of colored impregnations is about three millimeters, which ensures the preservation of the color range over a long period, regardless of the intensity of the abrasive effect. After applying the coloring mixture, the application of a water-repellent primer is required.

Examples of manufacturers

Below is a list of the most popular and high-quality impregnations:

1. The protector for strengthening the soil under concrete floors is endowed with high resistance to chemical environments, provides maximum strengthening of the concrete stone and allows you to remove dust from the surface. The hardener is used to create “breathable” floors. Ensuring high-quality adhesion between fresh and old concrete layers allows the Protector to be used for repairing surfaces. The anti-dust substance is suitable for the construction of roads, airfields, and sidewalks.
2. The inorganic dedusting mixture XTREME HARD is endowed with water-repellent properties. Silica dust is used for production.
3. Retroplate is a strengthening mixture that has a dust-removing effect on low-quality concrete and mosaic surfaces. Works only at temperatures above 5° and on mature concrete.
4. Probetil is a special strengthening material with universal properties. The direct use of probetil is the treatment of industrial floors, providing protection against aggressive influences and intense loads. The penetration depth of probetil is 5-10 mm with economical consumption.
5. Monolith 20-M is a universal water impregnation. Eco-friendly and non-flammable, therefore used in apartments. Penetrates 20-30 cm into the surface, maintaining air circulation in the pores. Dust removers increase the adhesion of concrete to paints and its durability.

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Tips for choosing concrete impregnation

When choosing impregnation, pay attention to the following points:

• mixtures for chemical hardening on a silicate basis make it possible to ensure effective dust removal at minimal cost, as well as intensive use of the floor covering;
• It is advisable to use polymer compositions based on epoxy fillers when the coating is exposed to aggressive environments and in order to ensure the presentation of the base.

When choosing a material for surface waterproofing, you should take into account its operating conditions and the features of the concrete structure

Safety precautions

Occupational safety when working with impregnations requires solving the main problem: to prevent the composition from getting on the skin, mucous membranes or inside the body. When working with materials, personal protective equipment is used. This includes workwear (cotton robes or suits), safety shoes with leather soles, cotton mittens, rubber gloves, and safety glasses.

If the composition gets on the skin, wipe it with a clean rag and wash with running water and soapy water . If contact with mucous membranes occurs, rinse with plenty of water and consult a doctor.

In addition, precautions must be taken:

• in rooms where impregnations are used and stored, the use of open flames and ignition sources is prohibited;
• If the container is metal and it is opened, you cannot use a tool that can produce a spark upon impact.

When working with polyurethane compounds, wear gas masks or respirators of grade A

General requirements for waterproofing and strengthening

When performing work, pay attention to the following points:

1. The compositions are applied to a pre-dried base.
2. Recommended room temperature for work is 20–25 °C.
3. The surface to be treated must have a temperature of more than 10 °C.
4. It is advisable to abrasively grout the base before waterproofing.
5. Peeling and cracking on the base are not allowed.
6. The use of personal protective equipment is mandatory.

Tools,

High-quality implementation of work requires the use of special equipment and tools.

Equipment for preliminary preparation of concrete:

• grinding machines - for large volumes of work, high-performance equipment with a power of up to 3100 W should be used. Such a tool is durable and will allow you to quickly carry out the entire range of preparatory activities;
• shot blasting, sandblasting machines – they work on concrete with high-performance machines with a hopper volume of at least 25 liters. Plus, you will need a compressor to connect. The average cleaning performance of professional devices is 5-10 sq.m/h;
• hard screed brushes;
• industrial vacuum cleaners - the equipment must have high suction power - not lower than 255 mBar. For large areas, a good volume of garbage bin - 50 liters - will not hurt. The brush of the machine must be strong and fit tightly to the floor;
• hand grinder - in some cases you cannot do without a compact tool. They work in hard-to-reach areas and at junctions. ;
• construction mixer - effective models with a power of 1400 W, capable of working in forward and reverse motion. Speed ​​430-700 rpm.

Painting tools:

• brushes – work on concrete with professional brushes based on synthetic bristles. This tool is suitable for applying any impregnation. It is necessary to choose only high-quality samples that do not leave lint;
• rollers - in the case of impregnations (epoxy, acrylic, urethane, etc.), wear-resistant rollers with medium or short pile (based on velor or sheepskin) work well;
• spray guns – for professional application of materials, multi-purpose professional spray guns with a pressure of at least 2 Bar and an air flow of 300-350 l/min are used.

Even a small hand-held device for working with concrete must be powerful - at least 700 W, with a grinding speed of 3000-4500 rpm

Means of protection:

• respirators;
• workwear;
• safety shoes;
• glasses;
• gloves.

Concrete impregnation - application technology

Carry out self-hardening of the surface as follows:

1. Prepare the primer mixture and working tools.
2. Prepare the surface by removing loose layers and sanding the base.
3. Mix the required volume of the mixture, following the manufacturer's recommendations.
4. Cover the base with an even layer of impregnation.
5. Apply a second coat after the previous one has completely dried.

The waterproof layer will dry in 10–16 hours.