The main enemy of building structures is moisture. Both atmospheric and ground water pose a danger to foundations. Waterproofing strip foundation with your own hands prevents problems during the operation of the building.

Why is insulation needed?

The concrete surface of the foundation must be protected from exposure to liquid. This is necessary to achieve the following results:

• preventing water from entering the basement or ground floor of the house;
• protection of concrete from washing out particles and aggressive environments;
• preventing the harmful effects of cold.

The simultaneous action of water and negative temperatures dangerous for the material. Capillary moisture penetrates into the thickness of the foundation and freezes there. Water is a unique substance, only it expands when it freezes. Thus, the pressure inside the underground wall increases, which leads to its destruction.

Types of waterproofing

Waterproofing strip foundations prevents harmful effects various types moisture on the structure. At the same time, a system of three types of insulation is used:

• Horizontal. Prevents capillary rise of moisture. The first layer is provided in the wall of foundation blocks just below the basement floor level. The second layer is performed higher, along the edge of the foundation. It is designed to protect materials with different properties (for example, concrete foundation and brick wall).
• Vertical. It can be external (in most cases) or internal (in special circumstances).
• Blind area. Necessary for removing rain moisture from foundations. It reduces the load on the vertical insulation. Executed from various materials respecting the slope. Recommended width is 1 m.

Waterproofing a monolithic strip foundation involves installing vertical protection along the entire height. A horizontal layer at the sole level is not provided. To protect the base from moisture, concrete preparation made from lean concrete (class B7.5-B12.5) is used.

Drainage will be an additional measure to protect the structure from moisture. It plays the role of waterproofing the base of the strip foundation and is provided 30 cm below the edge of the structure. The horizontal distance from the building is no more than 1 m. For drainage, pipes with a diameter of 110-200 mm (depending on soil moisture) are used, which are laid with a slope of 0.003-0.01.

All of the above methods are suitable for deep groundwater (more than 0.5 m from the base). If the groundwater level is high, it is worth thinking about using a different type of foundation, since measures to protect the structure in this case (water reduction, caisson construction) can be very expensive.

Building without basement

Insulation from moisture must be provided regardless of the presence of a basement. Here it is worth returning to the previous question “why is insulation needed?” Its purpose is to protect concrete and extend the service life of foundations; this is necessary for buildings with and without a basement.

Waterproofing a strip foundation without a basement includes the following measures:

• vertical insulation outside the building;
• insulation between the foundation edge and the building wall;
• waterproofing of the floor on the ground, which is connected to the previous one (together they form a closed loop);
• insulation of the foundation cushion (for prefabricated type of structure).

When making a foundation from concrete blocks, the foundation pad is insulated from moisture using a reinforced concrete joint 50 mm thick. The use of other materials here will lead to deformation of the foundation.

Waterproofing materials

Depending on the location of the insulation, they are used different materials. Liquid bitumen compounds are most often used as vertical protection. Such coating waterproofing applied in two layers and used when soil moisture is low. It is characterized by low cost and simplicity of technology. Disadvantages include fragility.

There are also other options for vertical insulation of foundation walls:

1. Plastered. At the same time it levels the surface and protects it from moisture. Such insulation can last 10 years; over time, cracks appear on the surface into which moisture penetrates.
2. Pasting. Various roll materials are used. The most inexpensive and unreliable option would be roofing felt. Also, more modern materials are common among builders: technoelast, technoNIKOL, linocrom and hydroisol. Effective membranes are used less frequently due to relatively high prices. For reliability, the adhesive insulation of the foundation is performed in two layers.
3. Penetrating. This type of insulation not only increases the resistance of concrete to moisture, but also its strength and durability. The compositions are able to penetrate to great depths and provide protection from water in any direction. This type has become widespread in the repair and restoration of old foundations.
4. Liquid rubber. Applied to the surface by spraying. It is characterized by high elasticity and the absence of seams. The disadvantage is the high cost.

At high groundwater levels, the screen method of vertical insulation is used. For this purpose, clay-based bentonite mats are used. Also in this case, an internal protection device is possible.

Horizontal waterproofing along the edge of the foundation is made from rolled materials. The most common were roofing felt, linochrome, waterproofing, etc. Laying rolled materials at the sole level is not allowed. Instead use:

• reinforced seam 50 mm thick between the foundation pad and blocks in prefabricated technology;
• preparation (from lean concrete) for the base of the foundation in monolithic technology.

There are five types of blind area around the perimeter of the building. Depending on the material, the slope in the direction from the foundation is selected:

• concrete 3%;
• asphalt concrete 3%;
• from crushed stone 5%;
• from paving slabs 5%;
• membrane (hidden) 3%.

The choice of material for the blind area depends on aesthetic considerations and financial capabilities. The most affordable option considered concrete or asphalt concrete.

Proper waterproofing of the foundation protects it from premature destruction. To guarantee reliable protection, all measures are carried out in a comprehensive manner.

At the construction stage of a building, many craftsmen make a gross mistake, which subsequently leads to a violation of the building's structure. This mistake lies in the insufficient and poor-quality arrangement of the foundation. This means waterproofing the strip foundation and basement, if any.

It is extremely necessary to complete this stage of work, since the impact of groundwater on the outside of the foundation is quite destructive. Especially when you consider that the chemical composition of groundwater can vary dramatically depending on the location of the house in relation to chemical or metallurgical industry facilities, agricultural activities, etc.

Important: the lack of waterproofing on the outer walls of the basement can at least lead to dampness in it. In the worst case, constant flooding and the resulting destruction of the premises will be its fate.

Waterproofing a strip foundation with your own hands is quite simple. The main thing is to understand the principles and technologies of performing work, as well as to know about all possible types and types of waterproofing. About this in our material.

It is worth knowing that you can choose a different group of materials to complete the work. They are:

• Coating;
• Rolled;
• Sprayable;
• Penetrating.

Depending on the type of materials chosen, waterproofing technology is also used.

Coating type insulation

For waterproofing strip foundations and basements, including in this case, bitumen-based materials or bitumen mastic are used. According to the type of materials, it becomes clear that the waterproofing of the strip foundation in this case is carried out by spreading mastic along the entire perimeter of the base.

To carry out work using mastic, it is necessary to perform a number of such actions:

• Free the foundation (basement walls) from debris, dust and dirt;
• Primer deep penetration coat the surface of the outer and inner walls of the foundation;
• After the primer has dried, use a special brush (mastic brush) to apply the mastic in an even, continuous layer so that there are no gaps in the waterproofing.

The advantages of waterproofing using the coating method include:

• Low cost of materials;
• Ease of work;
• Good elasticity of the finishing coating;
• Excellent waterproofing properties of bitumen;
• High adhesion of the coating to concrete.

However, such waterproofing also has disadvantages. The main one is the low service life of the material. Thus, the layer of bitumen mastic remains elastic and intact for only 6 years. Then it begins to crack, as a result of which groundwater still penetrates to the walls of the foundation. The problem can be solved by purchasing coating waterproofing materials with the addition of softening polymers.

In addition, the integrity of the coating layer may be damaged during backfilling of the foundation. Small pebbles can scratch the coating and depressurize it. They solve the problem by laying a protective layer of roofing felt or geotextile over the applied layer of bitumen.

Roll type waterproofing (adhesive)

Here, materials in the form of a roll are used to protect the foundation from moisture. It can be roofing felt, geotextiles, Aquaizol, Isoplast with Helastopley. Most often, such materials are used if it is planned to build a house without a basement. In this case, both horizontal insulation is used (coating the foundation plane before its contact with the walls) and vertical (applying rolled material to the base walls).

Roll materials are attached to the base of the building in two stages:

• Adhesive (using bitumen mastic as an adhesive);
• Floating (using a gas burner to melt the material and make it pliable).

The technology for installing waterproofing is as follows:

• The foundation walls are cleared of debris and treated with a deep penetration primer;
• Next, after drying, the walls are coated with bitumen mastic and sections of waterproofing material are applied, pressing them well;
• The waterproofing joints are overlapped by 15 cm, and to ensure a good fit, a torch is used to fuse the cuts together.

The advantages of roll waterproofing include:

• Long service life;
• Excellent waterproofing ability;
• Easy installation;
• High resistance to any type of mechanical impact;
• Reliability of the entire structure.

But it is worth remembering that rolled materials for waterproofing based on fiberglass or fiberglass have less resistance to deformation in contrast to materials based on polyester.

Penetrating waterproofing

This type of waterproofing of foundation and basement walls is considered one of the most effective, but also expensive. Here, the waterproofing material is based on a special mixture of cement, quartz sand and special plasticizing additives. The result is a plastic material that is applied by coating to the walls of the base and penetrates into all the pores of the base, forming crystalline solidification in the voids. They will push water away from the underground part of the building.

Penetrating waterproofing is widely used for treating the walls of basements and other underground tanks, and for treating foundations of any kind.

The advantages of this type of waterproofing include:

• High quality insulation from groundwater exposure;
• Excellent ductility during application;
• High wear resistance of the finished coating;
• Durability of the entire structure;
• Resistance to aggressive environments.

The technology of waterproofing using penetrating mixtures is as follows:

• The walls are completely cleaned and treated with a primer;
• After the primer has dried, the insulating mixture is applied with a special brush or from a spray bottle;
• The coating is allowed to dry completely.

Spray insulation

This method of waterproofing a strip foundation is one of the most modern. The method of applying insulation by spraying is widely used in roofing work, at repair work old waterproofing coating or to create a new first layer. In comparison with the mass of advantages, the sprayed mixture has one significant drawback - high cost.

The technology for creating a waterproofing layer by spraying is as follows:

• The walls of the foundation or basement are cleaned of debris, dust and dirt;
• The moisture protection agent is applied to the finished surface using a construction sprayer, forming a seamless, even coating;
• For greater reliability, the sprayed mastic is reinforced with a layer of geotextile.

The advantages of this method of waterproofing are:

• Long service life (50 years or more);
• High adhesion properties of the material to concrete;
• Simplicity of work, which saves labor costs and time on the construction site;
• Absolutely smooth coating without seams or joints, which prevents the slightest ingress of moisture onto the surface of the concrete base;
• Environmental friendliness and absolute non-toxicity of the material;
• Excellent elasticity that resists any small inclusions in the soil;
• High resistance to ultraviolet rays.

If the house is built without waterproofing the foundation

Important: waterproofing the base of a new building should be carried out during the construction stage. However, it happens that a house is purchased, but there is no insulation from moisture. In this case, it is possible and necessary to save the house. In this case, you need to act like this:

• The house or basement is completely excavated along the entire perimeter of the foundation. Moreover, you need to start from the corners, moving towards the walls of the base, so as not to disturb the strength of the building.
• Now you should clean all the walls around the perimeter from dirt and dust. This should be done exclusively without the use of moisture. It is important to free all recesses, cracks and pores of the base from soil, earth and dirt.
• All cleaned cracks should be filled with special tile adhesive or cement mortar.
• After the foundation or basement walls have dried, they should be treated with bitumen mastic.

Important: under such conditions it is better to combine vertical and horizontal insulation.

• Rolls of roofing felt or other insulation material are cut into pieces of the required size and, using a special gas burner, applied to the walls of the structure with overlapping joints. The pieces are placed horizontally.
• Now you need to apply another layer of material in the same way, but with a vertical orientation.

Important: at the corners of the building you should turn roll material and make overlaps. But, under no circumstances should you cut the waterproofing. This installation method will break the tightness of the foundation winding.

• Lastly, a drainage system and a blind area for water removal are formed.
• All that remains is to backfill the base with good compaction of the soil.

The destructive effects of moisture are prevented by waterproofing the strip foundation throughout the life of the house. The materials used, the methods of their application, and the durability of the protection may vary.

The choice is made taking into account the entire complex of conditions of the construction site - geology, climate, building density, neighboring buildings.

Protection from natural factors

Engineering-geological study of the site in combination with the characteristics of the climatic zone will determine the magnitude of seasonal fluctuations in the groundwater level (GWL).

The depth of occurrence is conventionally divided into two values:

• Above 2 m (high);
• Below 2 m (low).

During floods, heavy melting of snow, or after heavy rains, the water level in the ground can rise up to 2 meters. Seasonal variations must be taken into account at their worst.

The influence of reservoirs is felt at a distance of over 1 km from the place where the facility is built. The necessary waterproofing of a strip foundation is done with your own hands if the distance from its lower border to groundwater does not exceed 1 m.

Prospective accounting of changes

An important stage in choosing waterproofing before starting work is to make allowances for the future, to look a little further, after the house is built. The hydraulic component can be affected by:

• Increased pressure on the support due to dense construction of the site. The water will rise;
• Long-term cycle of changes in water saturation of layers;
• Changing the drainage system of neighboring areas (including the arrangement of catch basins, dams, wells);
• Disruption of the movement of high groundwater (creation of a monolithic obstacle to the flow in the ground on slopes) due to the new construction of houses with buried strip foundations.

Types of waterproofing

Moisture comes to the surface of the poured monolith from above (precipitation), from the sides, and from below. It is necessary to create a barrier to absorption in two directions:

1. Horizontal. Rolled materials cut off the capillary rise from the foundation to the walls, from the pillow to the concrete. The blind area needs to be used to prevent water from seeping from the soil surface to the concrete of the outer part of the foundation. For this purpose, a screed with a slope of 2÷3° must protrude beyond the roof cut by no less than 0.3 m. Drainage removes incoming water and prevents it from seeping through the bedding monolithic base at home and serves in tandem with the blind area, but at a buried level.
2. Vertical. Prevents groundwater from seeping into the foundation structure. Capillary insulation prevents water from entering the concrete, free-flow insulation protects against seasonal fluctuations in water saturation of the layers, anti-pressure insulation prevents the penetration of groundwater.

Doubts about the need for insulation arise at the stage subsequent to pouring non-buried tapes directly into a trench dug in dry ground. The presence of a cushion provides a break before rising drops of moisture. If the solution is placed in a form covered with film, the foundation of the constructed house will last a long time.

Horizontal waterproofing should be done in accordance with SNiP 3.04.01-87. Order waterproofing works for the foundation of the house, SNiP 3.04.01-87, SNiP 2.03.11-85, SNiP 3.04.03-85 are installed

Separation by application method

Depending on the consistency of the material, the application method can be:

• coating;
• spraying;
• pasting;
• impregnation;

Methods performed by certified specialists:

• injection;
• shielding.

If the capillary rise of moisture predominates on the surface of the house located underground, then coating, spraying, bitumen or polymer compositions (liquid rubber) is done. Whether the mastic is hot or cold depends on the composition.

Rolled materials (films, geotextiles, roofing felt) are glued to the previously prepared surface with an overlap, after heating with a burner, rolling out air bubbles with a roller.

Impregnating compositions penetrate deeply into the structure monolithic concrete(blocks) and create a water-repellent layer of vertical insulation from water of sufficient thickness.

If the house has a basement, cellar, ground floor, waterproofing vertical walls Tapes, after hardening, are required.

The injection method is used as a repair measure for cracked foundations or those with internal cavities. The method is expensive, but sometimes the only possible one, if there is no technical access to the surface to be repaired, or there is deep damage to the load-bearing belt of the house after it is built.

Shielding is an expensive, rarely used method. It consists of installing a protective casing made of special mats or plates.

Material selection

Qualities of the polymer material from which the foundation tape is waterproofed:

• Water repellency (hydrophobicity);
• Waterproof structure;
• Elasticity, adhesion after application to a rough surface;
• Adhesion to concrete;
• Manufacturability (quite easy to process, install under construction conditions, ability to join into a solid surface after soldering or gluing);
• Durability in the ground under repeated temperature fluctuations.

The most common brush coating materials are bituminous mastics. Do-it-yourself application allows you to thoroughly fill all surface pores with a fluid composition.

Cover all parts in 3-4 layers, allowing them to dry for a day at each stage. The advantages include the ability to carry out work independently, the maintainability of any individual section, and the availability of material.

When applying the hot method, it is necessary to observe safety measures and use personal protective equipment.

The use of dry plaster mixtures with hydrophobic additives for coating is possible if the composition is frost-resistant. However, even in favorable conditions, after 10-15 years, cracking occurs, requiring repair. Hydraulic resistance is not high.

Installation of material

If you apply roll materials, you won’t be able to do it yourself. Assistants are invited to this stage. SNiPs allow the use of:

• fiberglass;
• polyvinyl chloride film;
• brizol;
• hydroisol (gidrostekloizol);
• polyisobutylene.

When spraying liquid rubber, you must not only know how to use a sprayer, but also cover the resulting surface of the lower part of the house with geotextile for protection over the entire area. Can also be applied with a brush.

The materials are glued from top to bottom. Vertical rows must be made with a 0.4 m separation at the joints of the seams. At the next stage, the corners are armored, after closing the vertical walls, with the same sheet, 0.2-0.3 m overlapping in each direction. They use gas-flame burners, propane in cylinders and protective equipment.

Watch the video on how to waterproof a strip base.

Liquid rubber is not stored in its finished state. You need to calculate how much will be used immediately when you open the package or mix two component composition. Under the rubber you need a primer.

The service life will be 50-70 years.

Important points

According to GOST 12.3.009, the following rules must be observed:

1. The maximum moisture content of poured concrete is no more than 4%;
2. Waterproofing using spray or paint compounds is carried out after the primer has completely dried;
3. The thickness of the waterproofing layer ranges from 0.3 cm to 0.6 cm.

If the house is built close to the groundwater level, it is necessary to carry out lining work (SNiP 3.04.03-85). The protection is made from sheets of rubber and vulcanized at the joints.

How to make drainage

If there is a high groundwater level, heaving soil, horizontal waterproofing of part of the house includes a drainage system.

Watch the video on how to properly install strip base drainage.

Drainage happens:

• Annular. A distance of 5-8 m from the walls in the form of a solid or open circle.
• Wall-mounted. The distance from the walls is equal to the width of the foundation. The depth is no more than its depth.
• Plast. The pipes are laid under the building area.

The outlet pipes are laid in a permeable filler (coarse crushed stone, sand) and discharged into a drain tank, which must be built outside the site.

Foundation waterproofing in modern low-rise construction is an almost integral part of the zero-cycle construction process. This is due to the presence of moisture in the soil in the vast majority of territories of our country. Water itself is not particularly dangerous for concrete; on the contrary, in a slightly moistened state, concrete continues to gain strength over many years. However, there are three big “BUTs”.

Firstly, concrete has the property of capillarity. This is the rise of water up through the smallest pores located inside the material. The simplest example of this phenomenon is wetting a piece of sugar slightly lowered into a glass of tea. In construction, the capillary rise of water leads (unless, of course, waterproofing is done) to the penetration of moisture, first from the outer layers of concrete to the inner ones, and then from the foundation to the walls that stand on it. And damp walls mean increased heat loss, the appearance of fungi and mold, and damage to interior finishing materials.

Secondly, a modern foundation is still not concrete. This is reinforced concrete, i.e. it contains reinforcement, which upon contact with moisture begins to corrode. In this case, the iron in the reinforcement turns into iron hydroxide (into rust), increasing in volume by almost 3 times. This leads to the formation of strong internal pressure, which, when reaching a certain limit, also destroys the concrete from the inside.

Thirdly, we do not live in the tropics, and sub-zero temperatures for our climate in winter period- this is the norm. As everyone knows, when water freezes it turns into ice, increasing in volume. And if this water is deep in the concrete, the resulting ice crystals begin to destroy the foundation from the inside.

In addition to the above, there is another danger. It is not uncommon for groundwater in a site to contain chemical elements(salts, sulfates, acids...) that have an aggressive effect on concrete. In this case, the so-called “concrete corrosion” occurs, leading to its gradual destruction.

High-quality waterproofing of the foundation allows you to prevent all these negative processes. And how it can be accomplished will be discussed in this article.

By and large, you can protect the foundation from moisture in two ways:

1) when pouring, use the so-called bridge concrete with a high coefficient of water resistance (various grades of concrete and their characteristics will be discussed in a separate article);

2) cover the foundation with a layer of some waterproofing material.

Ordinary developers most often now follow the second path. What is this connected with? At first glance, it would seem that it could be simpler - I ordered waterproof concrete from the factory, poured it and that’s it, sit back and be happy. But in reality, not everything is so easy, because:

• price increase concrete mixture with increasing water resistance coefficient it can reach 30% or more;
• not every plant (especially a small one) can produce a grade of concrete with the required water resistance coefficient, and attempts to produce such concrete on your own can lead to unpredictable consequences;
• and most importantly, there are problems with the delivery and placement of such concrete (it has very low mobility and sets quite quickly, which in most cases limits the possibilities of its use).

The use of a waterproofing coating is accessible to everyone and, with certain skills, can be done even with your own hands.

Materials for foundation waterproofing.

All materials used to protect foundations from moisture can be divided into the following groups:

• coating;
• sprayable;
• roll;
• penetrating;
• plastering;
• screen waterproofing.

Let's take a closer look at each of them.

I) Coating waterproofing is a bitumen-based material that is applied to the surface (often in 2-3 layers) using a brush, roller or spatula. Such coatings are usually called bitumen mastics. You can make them yourself or purchase them ready-made, poured into buckets.

Recipe for homemade bitumen mastic: buy a briquette of bitumen, split it into small pieces (the smaller, the faster it will melt), pour into a metal container and put on fire until completely melted. Then remove the bucket from the heat and add waste oil, or better yet, diesel fuel (20-30% of the volume of mastic), and mix everything thoroughly with a wooden stick. How this is done is shown in the following video:

Ready-made bitumen mastic is sold in buckets. Before use, for more convenient application, it is usually mixed with the addition of some solvent, for example, solvent, white spirit, etc. This is always indicated in the instructions on the label. There are several manufacturers of such mastics with at different prices and various characteristics of the finished coating. The main thing when buying them is not to make a mistake and not take material, for example, for roofing coverings or something else.

Before applying bitumen mastic, it is recommended to clean the concrete surface from dirt and prime it. The primer is made with a special composition, the so-called bitumen primer. It is also sold in stores and has a thinner consistency than mastic. Coating waterproofing is applied in several layers, each of which after the previous one has hardened. The total thickness of the coating reaches 5 mm.

This technology is one of the cheapest compared to those described below. But it also has its drawbacks, such as the short durability of the coating (especially when prepared independently), the long duration of the work and high labor costs. The process of applying mastic with a brush is shown in the following video:

II) Sprayed waterproofing or the so-called “liquid rubber” is a bitumen-latex emulsion that can be applied to the foundation using a special sprayer. This technology is more progressive than the previous one, because allows you to perform work with better quality and in a fairly short period of time. Unfortunately, mechanization of work significantly affects its cost.

The characteristics of liquid rubber and the process of its spraying are shown in the following video:

III) Roll waterproofing It is a modified bitumen or polymer material, previously applied to any base. The simplest example is the well-known roofing felt with a paper base. In production more than modern materials Fiberglass, fiberglass, and polyester are used as a base.

Such materials are more expensive, but also much higher quality and durable. There are two ways to work with roll waterproofing - gluing and fusing. Gluing is carried out on a surface previously primed with a bitumen primer using various bitumen mastics. Fusing is carried out by heating the material with a gas or gasoline burner and then gluing it. How this is done is shown in the following video:

The use of rolled materials significantly increases the durability of foundation waterproofing compared, for example, with coating materials. They are also quite affordable. The disadvantages include the difficulty of performing the work. It is quite difficult for an inexperienced person to do everything efficiently. You also can't do the job alone.

The appearance of self-adhesive materials on the market several years ago made it much easier to work with roll waterproofing. How to protect the foundation with their help is shown in the following video:

IV) Penetrating waterproofing- this is a coating of concrete with special compounds that penetrate 10-20 cm into its thickness through the pores and crystallize inside, thereby clogging the passages for moisture. In addition, the frost resistance of concrete and its protection from chemically aggressive groundwater increases.

These compositions (Penetron, Hydrotex, Aquatron, etc.) are quite expensive and have not been found wide application for complete waterproofing of the foundation in a circle. They are more often used to eliminate leaks in already built and operated basements from the inside, when it is no longer possible to repair the waterproofing from the outside using other methods.

Learn more about the properties of penetrating materials and their correct use says in the following video:

V) Plaster waterproofing By and large, it is a type of coating insulation, only here it is not bituminous materials that are used, but special dry mixtures with the addition of waterproof components. Prepared plasters are applied with a spatula, trowel or brush. For greater strength and to prevent cracks, a plaster mesh can be used.

The advantage of this technology is the simplicity and speed of application of materials. The downside is the low durability of the waterproofing layer and lower water resistance compared to the materials described above. Usage waterproofing plasters it is more appropriate for leveling the surfaces of foundations or, for example, for sealing seams in foundations made of FBS blocks, before subsequently covering them with bitumen or roll waterproofing.

VI) Screen waterproofing- this is sometimes called the protection of foundations from moisture using special swelling bentonite mats. This technology, which is essentially a replacement for the traditional clay castle, appeared relatively recently. The mats are attached to the foundation with dowels overlapping each other. More details about what this material is and its properties are discussed in the following video:

How to choose waterproofing for the foundation?

As you can see, currently there is a huge amount of all kinds of waterproofing materials to protect foundations. How not to get confused in this variety and choose exactly what is suitable for your specific conditions?

First, let's look at what you need to pay attention to when choosing waterproofing:

• presence or absence of a basement;
• ground water level;
• type of foundation and method of its construction

The different combination of these three factors determines which waterproofing should be preferred in this case. Let's look at the most common options:

1) Columnar foundations.

can only be protected with roll waterproofing. To do this, cylinders of the required diameter are pre-rolled from it, fixed with tape, lowered into drilled wells, reinforcement cages are installed and concrete is poured.

The cheapest option is to use regular roofing felt. If it has sprinkles, it's better to roll it up smooth side outward so that in winter when the soil freezes, less soil sticks to it. It is advisable to ensure that the thickness of the waterproofing along the entire circumference is at least two layers.

When used for columnar foundation asbestos or metal pipes, they can first be coated with any coating bitumen waterproofing in at least 2 layers.

If you are going to build on pillars, before pouring it, for greater reliability, the tops of the pillars also need to be covered with coating waterproofing (even better, not as in the figure below, but directly from the ground). This will prevent possible capillary rise of water from the soil into the grillage.

2) Shallow strip foundations (MSLF).

inherently must always be above the groundwater level. Therefore, for its waterproofing, ordinary roofing material and bitumen mastic are quite enough to prevent capillary suction of moisture from the soil.

The figure shows one of the working options. Before installing the formwork, a folded roofing material with a small outlet is spread on the sand cushion. Then after pouring and setting the concrete, side surfaces the tapes are covered with coating waterproofing. Above the level of the blind area, regardless of what kind of base you have (concrete or brick as in the figure), cut-off waterproofing is done by gluing 2 layers of roofing material onto bitumen mastic.

3) Recessed strip foundations (house without a basement).

Waterproofing of a buried strip foundation, regardless of whether it is monolithic or made of FBS blocks, when the house does not have a basement, can be done according to the scheme shown above for MZLF, i.e. the bottom is rolled material, and the side surfaces are covered with coating insulation.

The only exception is the option when the foundation is not poured into the formwork, but directly into a dug trench (as you understand, coating cannot be done). In this case, before installing reinforcement cage and pouring concrete, the walls and bottom of the trenches are covered with rolled waterproofing with gluing or fusing joints. The work is certainly not very convenient (especially in a narrow trench), but there is nowhere to go. This was discussed in the article.

Also don't forget about the layer shut-off waterproofing above the level of the blind area.

4) Recessed strip foundations, which are the walls of the basement.

The use of coating and spraying materials for waterproofing basement walls from the outside is permissible only in dry sandy soils when the groundwater is far away and the high water quickly drains through the sand. In all other cases, especially with a possible seasonal rise in groundwater, it is necessary to do roll waterproofing in 2 layers using modern materials based on fiberglass or polyester.

If the foundation is made of FBS blocks, before waterproofing it, it is advisable to cover the seams between the individual blocks with a plaster waterproofing mixture, at the same time leveling the surface.

5) Slab foundations.

Foundation slabs (basement floors) are traditionally protected from moisture from below by gluing two layers of rolled waterproofing onto a pre-poured concrete preparation. The second layer is spread perpendicular to the first. This was discussed in more detail in the article.

To avoid damage waterproofing layer during subsequent work, try to walk on it as little as possible, and immediately after installation cover it with extruded polystyrene foam.

At the end of the article, let us pay attention to two more points. Firstly, when the groundwater level rises above the level of the basement floor, you need to make drainage (a system of drainage pipes laid around the perimeter of the house and wells for inspection and pumping out water). This is a big topic that will be discussed in a separate article.

Secondly, the layer of vertical waterproofing of the foundation requires protection from damage that can occur during backfilling and soil compaction, as well as during frost heaving of the soil in winter, when it sticks to the waterproofing and pulls it up. This protection can be achieved in two ways:

• the foundation is covered with a layer of extruded polystyrene foam;
• install special protective membranes that are currently commercially available.

Most builders prefer the first method, because... it allows you to “kill two birds with one stone” at once. EPS also protects waterproofing and insulates the foundation. The insulation of foundations is discussed in more detail

The stability and integrity of the entire structure directly depend on the strength and durability of the foundation. erected on this basis the building, and even, to a certain extent, the safety of the people living in it. That is why the process of constructing the foundation part of the structure is always focused Special attention, and only the best building materials are used for this.

However, no matter what high-strength materials have not been used at the “zero cycle”, they all have a common ruthless “enemy” - water, in one or another state of aggregation. Moisture can reduce the strength of the structure being created in a relatively short time, so do-it-yourself waterproofing is the most important step self-construction own home, which should never be overlooked.

Why is moisture dangerous for the foundation?

The water that is familiar to all of us, seemingly completely harmless to an amateur’s eye, can cause a lot of trouble to the foundation of a building:

• Firstly, it is known that water has the ability to significantly increase in volume when it transforms into a solid state - when it freezes. Penetrating into micropores and cracks of even the most durable structure when temperatures drop below 0º C, it is capable of expanding them, increasing in size, and sometimes literally tearing them into separate fragments.

• Secondly, the water on the surface of the earth contained in upper layers soil and even drop-down in the form of precipitation is never clean. It is always saturated in one concentration or another with very aggressive chemical compounds - industrial emissions, agricultural chemicals, waste oil products, car exhaust, etc. Such substances cause surface erosion of concrete, from which it loses its strength and begins to crumble.

• Thirdly, these same chemical compounds plus dissolved In water, oxygen activates corrosion processes on the reinforcement grid. Not only does the inherent strength of the entire reinforced structure decrease, it leads to the formation of internal cavities in the thickness of the material and ultimately ends in delamination of the upper layers of concrete.
• And fourthly, we must not forget that What water has a pronounced leaching property (how can one not remember the proverb - « water wears away stones). Constant exposure to even chemical clean water always associated with the gradual washing away of foundation material particles from the surface, the formation of surface shells, cavities, etc.

Water in the soil adjacent to the foundation can be in different layers and in different states:

• The upper, so-called filtration layer is water that falls with precipitation, formed from melting snow or simply from an external spill (usage water for domestic and agricultural purposes, accidental bursts of highways, etc.). Sometimes, if a high-lying waterproof layer gets in the way of absorption, then in a certain limited area a fairly stable horizon can form - perched water.

The saturation of the upper filtration layer of water is always highly dependent on the time of year, established weather, and amount of precipitation and is not a constant value. In addition to high-quality waterproofing, a well-thought-out storm drainage system will play an important role in reducing the impact of moisture from this layer on the foundation of the building.

• The upper layers of the soil always contain soil (ground) moisture, which is constantly retained there due to capillarity or the adhesive properties of the soil. Its concentration is quite constant and depends very little on the level of precipitation, time of year and etc.. It does not exert any dynamic, leaching loads on the foundation, and its negative impact is limited to capillary penetration into materials and chemical “aggression”.

To counteract ground moisture, a waterproof layer of waterproofing is sufficient. True, in excessively wet areas of the area, with a tendency to waterlogging, it will be necessary to provide a water drainage system.

• Underground groundwater is the upper aquifers characteristic of a particular area and its topography. The depth of their occurrence depends on the location of the water-resistant soil layers, and the filling capacity is quite strongly influenced by seasonal factors - abundant snow melting, prolonged rains or, conversely, established drought.

The depth of these aquifers and its seasonal fluctuations can be clearly observed in the nearest well - ordinary or technological drainage. In addition to direct penetration into the thickness of the foundation material, these waters can also exert hydrostatic pressure on the buried part of the structure. If such layers occur at a high level, the maximum amount of waterproofing work will be required with mandatory installation effective drainage sewer around the building.

What types of waterproofing are used to protect the foundation?

In order to prevent the negative impact of moisture on the foundation, the following types of waterproofing and other construction and installation works are used:

• Giving construction materials with additional water-repellent properties.
• Creation waterproof coatings on the vertical walls of the foundation, from its base to the top edge of the base.
• Reliable waterproofing of horizontal interlevel seams, preventing capillary upward penetration of moisture.
• Reliable protection of the waterproofing itself from external mechanical influences.
• Measures to reduce negative impact negative temperatures.
• Installation of a drainage system around the house.
• Creation of a reliable system for draining rain and melt water - drainage and storm sewerage.
• Ensuring reliable ventilation of basements and basements.

The proposed figure shows, as an example, a possible general scheme waterproofing the building foundation:

The diagrams are marked with numbers:

1 – the base of the foundation, which usually rests on a compacted sand and gravel bed. Between her and vertical wall foundation (2) there must be a cut-off horizontal waterproofing (4), which overlaps with the insulating layer arranged in basement floor rooms (4) between the base and the screed.

The outer vertical wall has a coating waterproofing coating (5), additionally protected by a waterproof membrane (7) and covered with a layer of geotextile (8), which protects against abrasive and other mechanical effects.

The upper edge of the plinth (foundation wall) is also necessarily covered with waterproofing roll material (6), on top of which further construction of the walls and ceilings of the building will be carried out.

Provided for moisture removal drainage system– pipes (9) laid around the perimeter at the level of the base of the foundation in a gravel cage. For more reliable protection against water from precipitation entering deep into the soil, it is advisable to arrange a clay castle (10).

In areas with a harsh climate, severe freezing of the upper layers of the soil, or in the case where residential or utility premises are planned to be located in the basement or basement, the waterproofing system of the foundation and basement is complemented by a system for their insulation:

The diagram in general terms repeats the one posted above, so the main numbering of parts and assemblies is preserved. In addition shown:

1.1 – sand and gravel cushion under the base of the foundation. This layer can also be made of lean concrete with coarse-grained filling.

12 – insulating panels made of extruded polystyrene foam, installed externally on top of rolled waterproofing along the entire height of the foundation and basement walls.

13 – plaster layer of the basement finishing. Currently, special base thermal panels are often used instead - they provide both insulation and reliable protection from direct exposure to water.

14 – wall of the building being erected. The figure clearly shows that it begins to be laid from the layer of horizontal cut-off waterproofing of the foundation.

The choice of a specific type of waterproofing, and therefore the materials used for it, largely depends on the specific purpose of the room located in the basement. Existing classification(according to European standards BS 8102) divides them into four classes:

• The first, lowest class is utility or technical premises that are not equipped with electrical networks. They tolerate wet spots or even small leaks. The wall thickness must be at least 150 mm.
• The second class also includes technical or utility rooms, but already equipped with ventilation, in which only damp vapors are allowed, without the formation of damp spots, with a wall thickness of at least 200 mm. It is already permitted to install electrical appliances of standard mains voltage here.
• Third class is the most common, and most of all of interest to individual developers. This includes all residential buildings, offices, outlets, objects of social and domestic sphere. The thickness of the walls should not be lower than 250 mm; a natural or forced ventilation. No penetration of moisture is allowed.
• As a rule, you don’t have to deal with the fourth class of premises when building your own home - these are objects with a specially created microclimate - archival storage facilities, libraries, laboratories and others, where special requirements are imposed on a constant, clearly established level of humidity.

The table below shows the recommended types of waterproofing and the materials used for its installation, indicating its degree of strength, the protection created from one or another effect of groundwater and compatibility with the classes of equipped premises:

Type of waterproofing and materials used	crack resistance	degree of protection against water			room class
		perched water	soil moisture	ground aquifer	1	2	3	4
Modern adhesive waterproofing using polyester-based bitumen membranes	high	Yes	Yes	Yes	Yes	Yes	Yes	No
Waterproofing installed using polymer waterproof membranes	high	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Coating waterproofing using polymer or bitumen-polymer mastics	average	Yes	Yes	Yes	Yes	Yes	Yes	No
Flexible coating waterproofing using polymer-cement compositions	average	Yes	No	Yes	Yes	Yes	Yes	No
Coating rigid waterproofing based on cement compositions	low	Yes	Not	Yes	Yes	Yes	No	No
Impregnating waterproofing, increasing water repellent properties concrete	low	Yes	Yes	Yes	Yes	Yes	Yes	No

After viewing the table, one can make a very erroneous conclusion that, for example, for a residential building, just one type of insulation will be sufficient. Practice shows that this may clearly not be enough, and is most often used A complex approach, when one type, combined with another, creates a truly reliable waterproof barrier for the foundation.

Horizontal waterproofing of the foundation

It is advisable to start the review with horizontal waterproofing. The fact is that it can be carried out exclusively during the construction of the building. If the vertical one can be carried out even on a fully constructed building, for example, after purchasing a finished house, then it is almost impossible to carry out the overlooked horizontal one - it is always planned in advance. There are, however, modern techniques injection waterproofing, but they are very expensive and still remain only a half-measure aimed at minimizing previously made miscalculations.

• The first unique waterproofing level is a compacted sand and gravel cushion under the foundation soles being laid or under the monolithic structure being poured.
• If it is planned to pour a concrete slab in a basement or basement room, then its first layer is also made over such a backfill, so that the level is equal in height to the top edge of the laid soles or the first layer of “tape”. Made from lean concrete. This is where the first layer of horizontal waterproofing is laid - the room is completely covered from below from the penetration of soil water. In addition, a barrier is created against the capillary rise of moisture along the walls of the future foundation.

• Waterproofing is carried out using roofing felt, adjacent sheets of which are laid with overlaps of 100 - 150 mm, with the obligatory “boiling” of them using a gas burner. If layers of roofing material are combined, laid on the floor and on platforms for further pouring of the foundation tape, then the overlaps are increased to 250 — 300 mm.
• It is recommended to spare no expense and perform such insulation even in two layers. In this case, the stripes of the second layer should be oriented perpendicular to the first.

The second “line of defense” against the capillary spread of moisture should be organized at the transition point monolithic foundation(after pouring it) into the basement part, if this is provided for by the project. The importance of this waterproofing layer is clearly demonstrated in the diagram presented:

Location of “boundaries” of cut-off horizontal waterproofing

For such waterproofing, the same roofing material is used, laid on a completely hardened and strengthened concrete base, cleaned of dirt and dust and carefully primed tar mastic. The material is laid in at least two layers by gluing them together with mastic or using a thermal method (fusion).

If the project does not provide for a separate base, and its role will be played by the protruding above-ground part of the monolithic foundation, then this step is understandably skipped. But in any case, exactly the same actions are taken along the upper edge of the foundation or plinth, regardless of whether floor slabs are laid on this basis or walls are built from any material.

Sometimes work on waterproofing the upper horizontal plane of the foundation is combined with similar operations on vertical walls, thereby obtaining one monolithic insulator surface.

Vertical waterproofing of foundation walls and plinth

Vertical waterproofing foundation walls is prerequisite for long-term trouble-free operation of the building. When building a new house, it is thought out in advance. It is also carried out on houses that have been built a long time ago - if there are obvious signs that the old waterproofing is clearly not coping with its functions - there are pronounced traces of moisture penetration into the premises, or if when purchasing a house there is no certainty that such work was carried out previously.

Spots like these are a clear warning sign

• To carry out such waterproofing work, it will be necessary to expose the foundation walls to the maximum possible depth - right down to its base. During construction, this factor is usually taken into account immediately, leaving the necessary trench around the perimeter - it will be needed both for waterproofing and for installing a drainage system.
• On an old building you will have to start with earthworks. First, the concrete blind area around the base is dismantled - using a hammer drill or manually. Then they dig deeper, going deeper to the bottom of the foundation. The width of the trench can be any - the main thing is that it allows you to freely carry out all the necessary actions. Usually a width of up to 1 meter is sufficient.
• The walls are thoroughly cleaned of soil residues and inspected.
• All loose areas, peelings, and unstable areas must be unconditionally removed. The surface must be cleaned to a monolithic structure.
• If a layer of waterproofing is applied to the walls, but its functionality is questionable, then it is also better to completely remove it.

Repair of wall surfaces and their impregnating (penetrating) waterproofing

• All cracks and cracks on the surface are cut into rectangular grooves measuring 25 × 25 mm along the entire length. Similar operations are carried out in places of vertical and horizontal joints of reinforced concrete blocks with the removal of old mortar. If the foundation is block or made of brick, the seams are cleaned to the same depth - up to 25 mm.

• As a repair composition, we can recommend the specialized waterproofing dry construction mixture “Penecrete”, which is used in combination with the deep penetration primer “Penetron”.

- "Penecritus" has good plasticity, high adhesion to almost all building materials, and after complete hardening it becomes reliable waterproofing agent, firmly “sealing” seams and cracks. It is important that after filling the seams the material does not shrink.

— “Penetron” or other primers of similar action penetrate deeply into the thickness of concrete, forming additional crystalline bonds there, which significantly strengthens the material, and firmly closing the pores, preventing capillary penetration of moisture.

The advantage of these materials is that they are applied to a wet surface, thereby reducing the time required for work - during construction there is no need to wait for the concrete to dry completely.

“Penecrete” is prepared in the usual way - like any dry construction mixture, using a construction mixer or drill with an attachment, in strict accordance with the instructions supplied with it. "Penetron" is sold in a ready-to-use form.

• So, all cut cracks, joints and seams are first moistened with ordinary water, and then primed"Penetron".
• Then, they are filled as tightly as possible, without leaving air “pockets”, with a repair composition - “penecrete” to the general level of the wall.
• After setting of the repair mortar over the entire surface external wall The foundation must be moistened (you can use a hose with a spray nozzle) and covered in two layers with the same deep penetration soil.
• If possible, then That Exactly the same operations are carried out on the internal walls of the foundation.

The created system of protection against moisture penetration is quite effective. There is even an opinion that she can single-handedly cope with the tasks of foundation waterproofing, and, carried out even on one side of the wall. Nevertheless, it is still better to use such an impregnation technology as the main one only from the inside and on the part of the foundation or plinth protruding above the surface of the earth. On the outside, it is still worth playing it safe and protecting the walls in the area of ​​their direct contact with the ground with additional waterproof layers.

Video: using penetrating waterproofing of the Penetrat system

Coating vertical waterproofing of foundation

Coating waterproofing of foundation walls is perhaps the most widespread technology among private developers. It is quite simple to implement - almost anyone can do it, does not require excessively high material costs, and does not take much time.

To work you will need:

- Bitumen primer - it can be purchased at a store in finished form(bitumen primers). It is not difficult to make it yourself - bitumen heated to a fluid state is mixed with a solvent, which is most often used as gasoline. The weight ratio of gasoline to bitumen should be approximately 1:3 ÷ 1:4. It is important that when preparing the primer, bitumen is poured into gasoline, and not vice versa. The composition should have an even liquid consistency, similar to regular paint.

Prices for waterproofing for foundations

Waterproofing for foundation

Step-by-step instructions for waterproofing a foundation with self-adhesive bitumen-polymer material “Technoelast-Barrier (BO)”

The table below provides an illustrated step-by-step instruction to perform waterproofing work on the foundation using rolled self-adhesive material on a bitumen-polymer basis, “Technoelast-Barrier (BO)” from the well-known Russian manufacturer “TechnoNIKOL”.

This rolled material (standard release form is a 20×1 m roll) is designed for waterproofing concrete slab bases, floors, and plinths, with a depth from the ground surface of up to 3 meters, and the absence of high groundwater. The convenience of “Technoelast-Barrier (BO)” is that its use does not require additional equipment, is not associated with “hot” processes, that is, there is no stage of melting using a gas burner - work can be carried out even on a flammable base, in enclosed spaces and limited spaces.

Prices for Technoelast-Barrier

TechnoNIKOL technoelast

Illustration	Brief description of the operation being performed.
	The material itself is a baseless structure, consisting of a top layer - a dense polymer film with the TechnoNIKOL logo printed on it, and a second layer - a bitumen-polymer viscous composite material that has excellent adhesion to prepared substrates. Before installing the material, this adhesive layer is covered with a special protective film backing, which is removed immediately before installation.
	The adhesive bitumen-polymer layer does not need to be subjected to thermal effects - the material is simply glued to the treated surface, and then straightened and rolled using wide brushes, rubber or silicone rollers, or hand rollers. Other tools you will need are a knife for cutting the material, a tape measure, a ruler, a square for taking measurements, marking and cutting, a roller and a brush for preliminary priming of the surface.
	Let's start our consideration with horizontal waterproofing. As already mentioned in the article, this could be, for example, slab foundation or the floor in the basement or basement. First of all, you need to make sure once again that there are no gross defects on the surface - potholes, cracks, sagging of hardened mortar and other serious flaws. All this must be eliminated - removed or repaired, achieving a flat surface, otherwise the chosen waterproofing method may become ineffective. The rolled material should adhere tightly to the surface over its entire area.
	It is easy to check the evenness of the surface for waterproofing by applying a long rule to it.
	Perfect evenness is not required - it is quite enough if the differences in a two-meter area are no more than 5 millimeters.
	In order for the primer to lay well and evenly on the surface, it must be cleared of small construction debris and dust. To do this, it is carefully swept...
	...and ideally, it is best to clean it and completely remove dust using a powerful construction vacuum cleaner.
	The next step is to apply a primer, that is, a special bitumen composition - a primer. However, there are certain restrictions on the use of various primers, depending on the moisture level of the concrete surface. Residual moisture is measured using a special device - a moisture meter. It is clear that not everyone has such a device. You can get by with more simple solution– place on fully matured concrete surface plastic film measuring 1000x1000 mm, gluing it around the perimeter with tape. If after 24 hours there are no drops of condensation on the film, then the concrete can be considered dry, with a residual moisture content of less than 4% by weight.
	In such conditions, you can use TechnoNIKOL primers No. 01 and No. 03 on an organic basis.
	If the residual moisture content of the concrete exceeds 4%, then you can use the water-soluble primer “TechnoNIKOL” No. 04. But even in this case, the humidity cannot be more than 8%, that is, the concrete must fully gain strength and mature. It makes no sense to carry out any waterproofing work on a foundation that has not met the entire period required for maturation.
	The primer is spread thickly and sparingly over the surface using a roller. The normal consumption is 300÷350 ml per square meter area.
	It is necessary to ensure that the distribution of the primer over the surface is uniform, without “bald spots”. IN hard to reach places, especially along the line of intersection of vertical and horizontal surfaces, you can’t do without using a brush.
	It is recommended that after applying the primer there is no long pause before laying the main waterproofing material. The only thing you need to wait for is for the applied primer to dry completely. It’s easy to check - press a regular paper napkin onto the treated surface, which already seems dry. If black marks remain on it, it is too early to proceed to further operations.
	But if the napkin remains clean after such an “experiment”, we can assume that the concrete surface is ready for basic waterproofing work
	The waterproofing roll is delivered to the work site. On a horizontal surface, you can mark a line along which the first strip of material will be laid.
	The outer packaging of the roll is opened and removed as unnecessary.
	The next step is to roll out the Technoelast-Barrier (BO) roll along the entire length of the area to be waterproofed. At the same time, it is necessary to adjust its position so that the spread canvas lies exactly along the intended line. Naturally, the rolling is carried out so that the polymer layer with the logo is at the top, and the protective film backing is at the bottom.
	After rolling out, the sheet is cut in place. It is best to do this along a ruler, using a sharp construction knife.
	After trimming, the canvas spread along its entire length must be carefully rolled from both sides to the center without moving its position. It is more convenient, of course, to perform this and all further operations together, together with an assistant.
	In order to prevent distortions in the direction and creases of the waterproofing material itself when rolling, it is recommended to use old cardboard sleeves as reels for these purposes.
	Now the final laying of the material begins. First, you need to cut the film backing material along the transverse line along the entire width of the roll. This must be done carefully, without pressing the knife, so as not to accidentally cut through the canvas.
	After this, along the cut made, the substrate is separated in a narrow strip from the adhesive surface of the waterproofing, also along the entire width of the roll.
	Now, gradually pulling out the backing film, the roll is finally laid out from the center in one direction. The adhesive bitumen-polymer layer comes into adhesive contact with the concrete surface coated with a bitumen primer.
	It is more advisable to do the work together: one worker, pulling out the film backing, gradually unrolls the roll. The second, without hesitation, immediately smoothes the laid canvas, expelling possible air bubbles from under it. The most convenient way to do this is to use a wide brush with a long handle, as shown in the illustration. Then the same operation is repeated in the other direction from the center. As a result, the first sheet is laid. For the central areas of the glued sheet, pressing with a brush (with a well-prepared concrete surface) is sufficient. But it is advisable to also roll the edges, in a strip of approximately 150 mm on each side, with a heavy metal or rubber roller.
	When gluing the next canvas lying parallel to the first, observe next rule– the overlap must be at least 100 millimeters. The overlap strip is rolled with a roller to ensure complete sealing of the sheet joint.
	Of course, when laying waterproofing, they try to use entire sheets along the entire length. But sooner or later a situation arises when you have to join two strips along the end edge. There are also certain standards here.
	Even at the stage of “trying on” the next canvas, the necessary margin for overlap is immediately laid down.
	The minimum width of the overlap strip should be 150 millimeters.
	But that's not all. If you get a T-shaped joint, that is, two sheets laid and connected along the end side simultaneously overlap along their long side with the previously laid sheet, it is recommended to perform another operation. On the sheet that ends up in the middle (that is, the edge lies on the previously laid sheet, and then overlaps at the end with the next one), it is necessary to cut off the corner.
	The dimensions of the legs of this removable triangle correspond to the above parameters for the overlap of the canvases along the length and at the end. A rigid lining is placed under the edge of the sheet, and the corner is cut off with a knife.
	After this, the final “assembly” of this connecting unit is carried out, which is then necessarily rolled with a heavy roller for reliable sealing. The cut of the middle sheet in the joint turns out to be “packed” between the upper and lower sheets, so that the tightness is fully ensured.
	If similar T-shaped connecting nodes are found on adjacent strips, then the distance between them should be at least 500 millimeters. By the way, in this illustration you can clearly see the same cut corner, covered with the top sheet and rolled with a roller (shown by the red arrow).
	The work continues in the same manner until the entire horizontal surface requiring waterproofing is covered. The waterproofing layer itself also needs protection. If it is not intended to be backfilled with soil (for example, this is the floor of a basement or basement floor, or monolithic slab foundation), then a reinforced concrete screed (the so-called screed without connection to the base, on a separating layer), with a thickness of at least 50 millimeters, must be installed over such waterproofing.
	Now we move on to vertical waterproofing of the foundation. This is usually a more complex operation, since the surface often has many intersections of planes, both vertically and horizontally. Work is always carried out in sections from bottom to top, that is, the upper canvases overlap the lower ones, allowing free drainage for moisture (the sequence and direction are shown schematically in the illustration). But before that it is necessary to carry out whole line preliminary operations - preparation of surfaces, formation of transition fillets, priming and creation of a reinforcement belt. Let's talk about everything in order.
	They begin again by checking the condition of the waterproofed surface. There should be no high sagging, bumps, dips, cracks and crevices, that is, anything that can interfere with the tight fit of the Technoelast-Barrier (BO) fabrics over its entire area, without leaving air voids.
	The requirements for level differences are the same as on a horizontal surface, that is, within 5 millimeters over a two-meter area.
	When vertically waterproofing the foundation, sharp fractures from top to bottom are completely unacceptable, that is, pronounced horizontal internal angles, which can become an area of ​​moisture accumulation. That is, along the line of intersection of the vertical and horizontal planes, it is necessary to take measures to straighten the fracture as much as possible. This is done by laying out so-called transition fillets. The cross-section and dimensions of such a fillet (at least 100 millimeters along each leg) are shown in the illustration.
	To lay out fillets, you can use a regular cement-sand mortar, for example, in a ratio of 1:3. But in this case, you will have to wait for the concrete to completely harden “in full,” that is, within 4 weeks. So it is better to lay out the fillets immediately after removing the formwork from the foundation slab and discarding the soil from it. The optimal solution would be to use a special polymer-cement based building mixture, intended specifically for waterproofing work - it will create a reliable barrier against moisture in this vulnerable place, and it hardens and gains strength very quickly. The composition is diluted and kneaded in accordance with the instructions attached to it.
	The dry mixture is poured into the required measured volume of water and mixed until completely ready - obtaining a homogeneous plastic consistency.
	Then, using a regular spatula, fillets are formed, adhering to the dimensions indicated above.
	The laid fillets are left until they dry completely and gain strength.
	This illustration clearly demonstrates that fillets are laid out at all internal corners of the transition from the vertical to the horizontal plane. After the fillets are completely ready, they move on to the next stage of work.
	The next step is to thickly coat the entire surface for waterproofing with primer. On large areas it will be more convenient to work with a roller.
	But all difficult areas of the surface - external and internal corners and fillets - must be coated with a brush, so that not the slightest gap remains untreated with primer. Subsequent operations are carried out after the primer has completely dried - how to check this has already been described above.
	Next comes the most important stage - the creation of the so-called reinforcement belt. Its essence lies in the fact that all “problem” areas, without exception, are initially covered with strips of material, and only then, on top of the reinforcement, will the main waterproofing layer be installed. As already mentioned, the work is carried out from the bottom up. It often happens that work starts from an already waterproofed horizontal base. Another option is that the lower part of the structure consists of a concrete foundation preparation. It will have to be covered with material along its entire width, while adhering to the rules that apply on horizontal surfaces (see above). The illustration, just as an example, shows a belt of horizontal waterproofing 300 mm wide - it is assumed that the surface of the concrete preparation of the foundation has been covered. In the event that such a structural element is not provided (the tape was poured directly onto the sand and gravel bed), then the task is simplified. Our example shows probably the most difficult option, with two fractures of the waterproofing surface at different levels.
	When creating reinforcement on any of the fillets, cut out a sheet of such width that there is a strip of at least 100 mm wide on both the top, on the vertical plane, and the bottom, on the horizontal plane.
	As a rule, all elements are cut out and tried on manually, directly at the site of future installation. After adjustment, the fragment is immediately glued to the specified area.
	The scheme of actions is simple: the protective backing is removed from the cut fragment sequentially as it is glued. Any glued element of the reinforcement belt is immediately rolled with a rubber or silicone roller.
	Further, the illustrations show some techniques for gluing waterproofing to various areas reinforcement belts. The strip is glued to the outer vertical corner. The rule is still the same - when moving to different planes, the minimum strip width on each of them should be 100 mm.
	"Sole" of the outer corner.
	The inner vertical corner is covered. Naturally, work on creating reinforcement from below should already be completed.
	The upper protruding part of the strip, covering the inner corner, is cut in two, and the “petals” are spread apart.
	The remaining gap between them is sealed on top with a small square fragment of waterproofing.
	Following the basic rules, they waterproof all “problem” areas. Of course, a certain amount of intelligence will be required, making decisions applicable to the specific conditions of the work. In the example under consideration, the finished reinforcement belt looks like this.
	After this, they move on to gluing the main layer of waterproofing. It is recommended to adhere to the rule - no glued canvas should have more than one change in direction, otherwise it may become deformed with the appearance of voids. The work is carried out according to the same principle - from the lower sections to the upper ones: fitting, cutting, and then the final gluing of the fragment are carried out. The overlap on the end part of any fragments should be, as with horizontal waterproofing, at least 150 mm, on the side - 100 mm.
	In this case, the lines of vertical joints at adjacent levels must be spaced at a distance of at least 300 mm.
	The illustrations below show examples of gluing basic waterproofing. The sheet is tried on and cut to cover the horizontal “step” and the one located below vertical wall foundation slab.
	Unlike the technology of gluing waterproofing using the fusing method, in this case each of the canvases will be attached after fitting from top to bottom. At the top, the protective backing is removed and the canvas is fixed to the surface.
	For secure fixation top part You can immediately roll it with a roller.
	Then, carefully removing sequentially protective film, gluing the rest of the cut fragment is carried out.
	They move to the next section of the same level - and continue in the same sequence.
	In areas of large overlap of sheets at the bottom at the inner corners, trim the top sheet diagonally, as shown in the illustration.
	Then this unit is glued, followed by rolling with a roller.
	After complete completion of work at this level, they move higher - to a vertical straight section of the foundation strip. Waterproofing is carried out in compliance with the same rules and technological techniques.
	The glued waterproofing sheets must be fixed along the top edge. For this, an aluminum fixing profile is used, which is attached to the foundation strip with dowels through the holes on it. There is a bend on the profile - it should be located on top in the direction from the wall.
	The profile is tried on and cut off at right size, then holes are drilled in the wall, dowels are driven in and screwed in. Two dowels are placed along the edges of the profile, that is, in the first two holes in a row. Further installation proceeds in increments through one hole.
	If joining of two profiles is necessary, then a compensation gap of about 8 ÷ 10 mm must be left between them.
	After all the planks around the perimeter of the foundation are secured, the gap between the bent edge and the profile wall is tightly filled with polyurethane sealant using a construction syringe.
	As a result, the completely waterproofed surface of the strip foundation looks like this. However, it must be protected from mechanical damage when backfilling the soil.
	For this purpose, extruded polystyrene foam boards can be used. It is rigid and strong enough to withstand mechanical loads, and the foundation strip, among other things, also receives good insulation.
	Another option, when insulation is not required, is to use a special profiled membrane “PLANTER - standard”. It is characterized by high strength, elasticity, and raised “bosses” provide the necessary damping effect when backfilling soil.
	This membrane is attached to vertical surface foundation strip immediately in front backfill pit. In this case, its relief protrusions should be facing towards the waterproofed surface. At this point, the work on waterproofing the strip foundation can be considered complete.

There are other methods of waterproofing foundation walls - cement-polymer plasters or coating compositions, solid polymer membranes, bentonite mats, similar in principle to “ clay castle", deposition. However, in the conditions of individual construction, those mentioned in the publication are more often used.

Video: waterproofing the foundation by fusing rolled materials

And lastly, waterproofing the foundation will be effective only in those conditions where a well-thought-out management of storm and melt water is provided - drains from the roof, ebbs on the base, ground or underground storm inlets and drainage channels, etc. If water has direct access under the walls of the building, then sooner or later it will “do its job” and the reliability of the foundation’s waterproofing will be compromised.