Waterproofing a foundation made of FBS blocks can be carried out in several ways. Let's look at some of them in this article.

It is worth noting that the choice of waterproofing method must be entrusted to experienced specialists who will take into account multiple factors, incl. type building structure, type of adjacent soils, presence of underground water layers and much more.

Waterproofing by injection method

To carry out work on waterproofing a foundation made of FBS building blocks and reinforced concrete, you need quite expensive specialized equipment, which includes an injection pump capable of pumping up pressure up to 250 bar, as well as steel parkers with a special collet head. In addition, the participation of highly qualified specialists is necessary here, and therefore it will not be possible to do it on our own.

This type of foundation waterproofing is highly effective, although it requires significant investment, which pays off due to reliability and long service life, which is not possible when using other waterproofing materials on the market.

Let us briefly summarize the stages of waterproofing foundations made of FBS blocks using the injection method:

• Joint joints of installed FBS blocks 30-50 mm deep.
• Drilling holes in increments of 200 mm and a depth of 2/3 of the thickness of the foundation walls.
• Installation of injection parkers.
• Filling the seams between FBS blocks with special modified polymers, for example, MEGARET-40.
• Injecting the structure with a hydroactive composition using an injection pump.
• Removal of parkers.
• Sealing injection holes.
• Installation of coating waterproofing of the surface of foundation walls.

Foundation waterproofing with Penetron

Waterproofing of foundations made of FBS blocks is also carried out with Penetron. Let us briefly consider the main points on its use and the types of work that must be carried out before applying it.

If a layer of plaster was applied to the walls made of FBS blocks, then using a hammer drill or other available means we completely remove it. If the basement has floors, for example, wooden ones, then we proceed to completely dismantle them to the base of the foundation.

Every house must have a foundation. Without it, any structure will quickly settle and eventually crack and even collapse. In order for a building to last longer, it must be placed on a foundation. This will help in its long-term, groundwater will not cause harm, as they would do every autumn and spring season, if there were no foundation. To maintain the longevity of the structure, it is better to use waterproofing.

Foundation waterproofing

For those who are thinking for the first time about whether they need to do waterproofing, we will answer right away - of course, it is necessary. After all, we are talking about protecting the surface of the supporting structure. Almost always this is a basement wall or wall ground floors. One of the building materials that is used for protection is aerated concrete. Waterproofing of aerated concrete most often occurs on FSB blocks.

There are two types of waterproofing:

• vertical;
• horizontal.

The vertical type requires a lot of work, but the result is worth it. They start from laying the foundation, to those places where rain or other water waste may leak. The entire foundation row is cleared of various types protrusion and chips. All seams are cleaned and sealed.

In the horizontal type, everything is much simpler. Waterproofing aerated concrete blocks occurs due to the overlay of layers consisting of roofing felt sheets, which are made of bitumen. They are folded step by step into balls. Such balls of roofing material act as a shield to prevent any moisture from penetrating to the surface of the foundation block.

It is necessary to waterproof surfaces in the middle of the structure and on the surface. All work must be done at the same temperature balance, preferably at least 5 degrees.

And in this case, there is a need to clean all the protrusions, remove dirt, chips, and also seal the seams, treat everything with cement. Sometimes they use the method of applying liquid glass to the surface, which makes it possible to maintain the durability of the structure a little longer. And although this method is labor-intensive and expensive, its results are worth it.

Variations with waterproofing work

One of the waterproofing layer options is applied to the foundation block:

• plaster layer;
• pasting layer;
• coating layer.

Type of plaster layer: this composition contains a part of cement mortar with several layers, to which certain additives are added - ceresite, any version of liquid glass, sodium aluminate. The foundation wall is protected from any wet penetration of aerated concrete blocks. Apply several times and only when hot.

Type of adhesive layer: budget option. It is also not labor-intensive. Waterproof material made of polymer-bitumen composition. Protects against moisture, both capillary and filtration. One of the simplest ways to waterproof aerated concrete blocks. The components are heated on the burner.

Having received the hot state of the composition, it is applied to external foundation. Sometimes, when waterproofing adhesive type, materials with a dark-skinned surface are used. Then there is no need to heat the material.

Materials with a darkening surface:

• roofing felt;
• hydroisol;
• brizol;
• isol.

Ruberoid is used in the surface layers of the foundation roof. Waterproofing material is used around the perimeter. The waterproofing agent contains fiberglass material, which prevents the possibility of destruction due to the influence of fungi and rot.

One type of insulation is vertical insulation of foundation blocks. One of the most technologically difficult, but effective, injection waterproofing, increases the level of moisture resistance of the foundation material. Waterproofing by injection consists of filling microcracks, seams, holes special composition under pressure.

This method of performing work requires quite a lot of resources and rare, expensive equipment. But high cost covered with strength.

Waterproofing foundations consisting of FSB blocks consists of the following steps:

• the seams of the blocks are embroidered to a depth of 50mm;
• a drill is used to divide holes in increments of 20 cm, reaching 75% of the wall thickness;
• parkers for injections are installed;
• a special modified polymer is poured;
• the procedure is performed with a pump for this type of work;
• parkers are removed;
• the holes are sealed flush;
• Coating water-repellent insulation of foundation walls is produced.

The second method is to carry out waterproofing work using the Penetron mixture.

Water repellent is done as follows:

• clean the plaster layer from the walls using a chipper, a hammer drill, or a stiff wire brush;
• concrete walls are cleaned of remnants of tiles, dirt, paint layers, greasy stains, oils - nothing should interfere with the adhesion of the mixture to the wall. If we have polished surfaces, we etch them with a weak acid solution for an hour and a half and then wash them with water.
• floors in basements and basements are being dismantled.

Then the floor must be strengthened horizontally, for which a reinforcement network is used. The ends of the mesh are connected with reinforcement ties.

After strengthening the mesh to horizontal surface the structure is filled with a pre-prepared sand-cement mortar to which crushed stone is added.

Preparatory work waterproofing consists of the following steps:

• removing the cement mixture from the joints of the brickwork material;
• areas of possible leaks are sealed with a quick-setting sealant from Penelag, which hardens very quickly. To prepare Penelag you need:
• dry mix Penelag;
• water.

The mixture is combined with water in a ratio of 0.15 liters of water per 1 kg of mixture. The temperature of the mixture should not be less than 20 degrees Celsius.

Step by step mixing:

• The mixture is thoroughly mixed to a paste-like mass, smooth, uniform consistency.
• Due to the fact that the mixture hardens quickly, there is no need to prepare a large amount at once. The time for using the solution does not exceed 30 seconds before setting.
• Then all connecting surfaces are treated with an additional penetrating waterproofing material, Penetron. The material is applied with a wide brush or brush.
• Then the dry Penecrit mixture is diluted.
• To do this, prepare identical containers with measuring marks and a clean plastic container in advance.
• For mixing, use a drill or construction mixer.
• If small volumes are mixed, mixing is done by hand with mandatory hand protection with rubberized gloves.

Making the mixture

The mixture is prepared at the rate of 200 grams of water per 1000 grams of Penecrit. It is necessary to thoroughly stir the composition until a thick, creamy mass without lumps is obtained. This composition is also prepared in small quantities. It is necessary to strictly maintain the proportions, since the difference between the material is that it achieves plasticity with constant stirring.

The longer the mixing process, the more plastic the composition will be. The period of use of the composition is no more than thirty minutes. The suture grooves between the FBS blocks are treated with special care with this composition.

After finishing the work, the foundation walls are moistened, then they should be covered again with Penetton using a large brush or brush. painting works. The solution is used to insulate floor surfaces.

Other types of insulation

In addition to expensive injection insulation, you can use coating or cut-off horizontal insulation to protect foundation blocks.

For coating insulation, hot bitumen or mastics based on it are used. Bitumen, creating a film on the surface, seals pores, cracks, holes in FSB blocks, creating an impenetrable barrier for water.

Insulation of foundation wall blocks is carried out as follows:

• the surface is thoroughly cleaned of dirt, soil, concrete humps;
• carefully isolate the cracks with a solution of cement and sand;
• prime the surface of the walls;
• the first ball of heated bitumen is applied to the dried layer;
• after the first ball of bitumen has completely dried, a second layer is applied with strokes perpendicular to the strokes of the first layer to create a durable coating;
• For proper effect, such a coating should not have a thickness of less than three millimeters in one ball.

Working with hot bitumen is quite dangerous due to its heating to a temperature of at least 120 degrees for work. Hardening takes place very quickly, so it only takes 4-5 minutes to apply to the wall. If it's cold enough outside, working with a hot compound is very inconvenient.

Cold bitumen mastics are much more effective in this case. This mastic contains polymers, which makes it plastic.

The most modern material for coating is penetrating waterproofing with penetrating compounds. The composition is based on cement, quartz dust, and polymer additives. When the mixture is applied to concrete, it gets inside due to capillary suction and crystallizes in the pores of the concrete. As a result, after the mixture dries, we obtain a monolith that is one third stronger concrete base. As water tries to penetrate deeper, the concrete becomes even stronger.

Dry penetrating mixtures are sold dry in bags and diluted with water to the consistency of thick sour cream. The composition should be easily applied with a brush or brush. When working, you need to observe a time lag of 30 minutes, since the solution sets quickly. It is strictly prohibited to dilute the solution.

E The steps for foundation waterproofing with penetrating insulation look like this

• the foundation is cleared of dirt:
• wall blocks are cleaned of remnants of paint, plaster, and old coatings;
• if the surface of the old foundation coating is glossy, it is treated with acid for several minutes;
• The surface must be damp when applying the waterproofing solution.

The solution is applied manually with a brush or roller in several layers. The full effect of waterproofing with a penetrating mixture is visible after a few days.

Video: waterproofing a foundation made of FBS blocks

All known methods FBS waterproofings are intended not to eliminate moisture in any particular place of the building, but to comprehensively protect load-bearing structure building, without which he simply cannot exist. Modern industry is constantly developing new compounds to protect structures and foundations.

Millions of thousands of drops from all streams and rivers, after snow and rainfall, tend to hide in the thickness of the earth's crust. This water wealth is valued by agronomists in steppe and semi-desert areas. The amount of moisture that plant roots receive directly determines what the harvest will be like. The presence of water in the earth's crust is 14 times less than in all oceans, therefore it is stored like underground wealth. But this is on a national scale. When it comes to a house built with one’s own hands, a person changes his attitude towards groundwater. Moisture comes from almost all sides and imperceptibly destroys the foundation blocks and the house created with your own hands. Sometimes the destruction cannot be restored even major renovation. Conclusion: it is better to prevent sad consequences.

To do this, you need to pay attention to the strip foundation. Moreover, from the very first steps, when the foundation is laid and the first wall panel is constructed. The base, made with your own hands, must be durable and last for many years. Subsequently, it is more difficult to calculate and repair blocks buried in the ground. Therefore, the construction of the foundation will require a lot of money and correct calculations.

Water washes out the main components from concrete and, as a result, leads to corrosion of embedded reinforcement products. Wall structures lose their load-bearing capacity over time; there is no need to talk about the durability of FBS. Further, the inhabitants of the house discover not only the foundation damaged by moisture, but also internal communications and room furniture. Mold and fungi caused by moisture spread along walls, floors and ceilings. The house and foundation are collapsing - the calculation was wrong. The owners, turning to the craftsmen, learn that waterproofing will help protect their home from the destructive power of moisture. Then no repairs will be needed.

Types of FBS waterproofing

In the old days, people didn’t think much about the materials needed for waterproofing. They removed birch bark from the snow-white trunks of birch trees and laid it on the foundation: it does not rot and does not let water into the house. Currently, they are easily replaced with rolled bases such as roofing felt. If the house has no basement, then horizontal waterproofing receives paramount importance. This will prevent repairs. To protect the vertical surfaces of foundation blocks, insulation is applied to the internal and external planes of the foundation. Based on the methods of its application, the following varieties are recognized: coating (painting), penetrating, pasting, mounted (screen).

The first type involves the application of several waterproof layers that are firmly held on the vertical surfaces of the FBS. Progressive foundation materials for this are cement and polymer-cement mortars, which are easy to use and waterproof. The main advantage of penetrating waterproofing is the protection of blocks from the inside when moisture enters from the outside. It is used in semi-basements and basements. Pasting will help avoid repairs and is suitable for those who rely on low price and ease of application. However experienced craftsmen When making repairs, they say that roll materials are capricious and difficult to lay. Mounted is rarely used when installing FBS and wall slabs; it involves the creation protective screens. Traditionally they were created from clay, and in recent years- made of polymer geomembranes.

Holland and St. Petersburg like another type of waterproofing of buildings - injection: through holes located in the FBS and walls, cement mortar or liquid glass with a hardener from the inside of the building outwards, into the space between the soil and the foundation. This block insulation is expensive and requires special equipment.

When thinking about choosing the type of waterproofing for blocks, thinking about their repair, one must be guided by the chemical composition and level of soil waters, which interact with mineral and organic particles, ultimately changing their own composition and concentration.

Selecting suitable materials

Ruberoid, profiled membranes, liquid rubber, plaster compositions- what kind of materials are not offered for! What is suitable for a particular foundation is determined by the climate of the area where the house will be built or repairs done with your own hands. These include air humidity, rise groundwater, probability of precipitation. The higher the degree of their impact on the house, the more powerful the material and the more accurate calculations need to be used. One of the frequently used materials of our time is bitumen overlay material. It is affordable, versatile, resistant to mechanical stress, as well as static and hydrostatic pressure. In addition to its main property, low water absorption, it has flexibility: it can be attached by free laying directly on the base in a continuous direction in one layer. You can protect the basement from the outside using a waterproofing membrane. It will create an obstacle to water and drain it from the soil into the drainage.

Waterproofing mastics, which do not contain harmful toxic substances, are also considered popular materials for FBS insulation. However, be careful! It is better to work with them outside, as they are flammable. Where the soil is especially wet, you can cover the blocks with roll materials yourself, using several layers. All components must be secured with mastic.

To carry out waterproofing you will need the following tools and materials.

Materials:

• concrete;
• cement;
• bitumen mastic;
• used machine oil;
• roofing felt;
• geotextiles;
• gravel or crushed stone.

Tools:

• shovel;
• concrete mixer;
• sieve;
• bucket;
• roller or brush;
• gas burner.

Expensive but durable liquid glass is among the favorites; it can be replaced by penetrating treatment of the foundation with a special solution.

Initial calculation

Before laying a foundation of blocks, you should take into account that it is necessary to carry out waterproofing. To implement it, it is important to make a calculation and identify: at what level the groundwater is located, what forces of soil swelling are observed in the post-frost period, how heterogeneous the soil is and what are the conditions for using the building. If the highest level of soil water is located below the base of the foundation at a distance of more than 0.9 m, then you can make a vertical coating waterproofing, and the horizontal one should be made using a material such as roofing felt. If the water level is higher, but does not reach the basement level or rarely reaches it, then you need to make the insulation yourself more reliable. Perform the horizontal layer in 2 layers, covering with mastic. For vertical applications, use coating and pasting methods. As an addition, you can treat the foundation blocks and basement with penetrating waterproofing. If it often rains in the area where the house will be built, you will have to make a drainage system around the building. If we take into account the economy of the material, it is better to choose bitumen. A complex of different types of insulation will require large investments.

Horizontal insulation FBS

Tape and monolithic foundation require insulation to be made at or below the level of the basement floor by 10 cm, both in the basement and in the place where the foundation joins the wall. Clay should be poured into the bottom of the pit and compacted. Fill the top with concrete. After 10 days, treat it with bitumen mastic and lay roofing material on it. Then lubricate the surface of the foundation blocks with mastic again and lay the roofing material. Fill the top with concrete, which must be leveled and reinforced. The second thing to do is this: after 2 hours, pour sifted cement on top of the concrete and level it. After it gets wet, they act in the same way as with a concrete screed. When the strip foundation is completed, it is waterproofed again. To do this, the blocks are covered with bitumen mastic and roofing material is laid on top. The procedure is performed 2 times. The edges of the rolled material, which hang from the FBS, are brought down and pressed down with vertical waterproofing.

Foundation insulation diagram.

Waterproofing may require the presence of a drainage system if the ground water is high and the soil permeability is insufficient.

To arrange it, dig a trench around the perimeter of the house at a distance of 0.7 m from it. The depth is determined by the water level. The width is approximately 40 cm. The trenches should be located with a barely noticeable slope towards the storage pit. Geotextiles need to be laid on the bottom, the edges are wrapped around the sides of the trench by about 90 cm. A layer of gravel is poured over the entire trench. Then special perforated drainage pipes. A layer of washed gravel (20-30 cm) is poured again. They wrap everything in the remaining edges of geotextile and take the pipes into a collection pit. Next they are covered with soil.

Insulating vertical

You can do this waterproofing yourself, based on an individual calculation. Blocks and materials may be different.

The most standard method is to coat the strip foundation or blocks with bitumen resin. Pour 70% bitumen and 30% used oil into a bucket. Then heat the bitumen to a liquid consistency and apply 2 layers onto even blocks.

The total thickness should be 5 cm. To extend the life of this insulation, bitumen-polymer mastics can be used for FBS.

Additionally, the blocks can be covered with a material such as roofing material with your own hands, having previously treated them with bitumen primer or mastic.

Then heat the roofing felt gas burner and attach it to the foundation with an overlap. You can fix the roofing material using adhesive mastics. Then cover the top with bitumen again and stick on roofing felt.

The durability and reliability of reinforced concrete wall blocks largely determine their widespread use in the construction of strip foundations. Laying work finished products significantly reduce construction time, eliminating the labor-intensive processes of constructing a reinforcing frame, formwork, as well as preparation and pouring concrete mortar. In addition, their installation can be carried out regardless of weather conditions.

FBS blocks must be carefully isolated from the destructive effects of moisture contained in the soil. The hygroscopicity of unprotected concrete leads to corrosion of the material itself and the material embedded in it. metal fittings, which over time leads to loss of strength and destruction load-bearing base buildings.

Types of waterproofing

Some calculations based on the provided characteristics of the soil layers lying on the construction site, the groundwater level, freezing depth and average annual precipitation will help you avoid making a mistake in choosing a method for waterproofing FBS blocks. Relevant reference books and standards that regulate the use of certain materials and determine the waterproofing technology for a specific foundation will provide all possible assistance in resolving the issue.

Waterproofing for foundations made of FBS blocks is carried out in two directions:

• horizontal;
• vertical.

Horizontal waterproofing is required at the level of the base of the foundation and at the junction of the blocks with the walls. It is installed to protect structures from capillary penetration of moisture from the ground below. Vertical waterproofing is necessary to protect the side surfaces of foundation walls.

Waterproofing work must be carried out at the stage of foundation construction, since subsequently its implementation will entail large financial costs.

The installation of waterproofing is especially important during the construction of recessed basements under the building. In this case, it is not recommended to neglect its application on internal surfaces foundation walls. Double protection prevents the accumulation of condensation and the development of fungal mold.

Organization of horizontal waterproofing

Depending on the structure of the soil layers, as well as taking into account the height of the groundwater rise, strip foundations from FBS blocks are laid on different types grounds:

• monolithic concrete screed;
• crushed stone-sand cushion.

Finished surface concrete screed treated with bitumen mastic followed by laying roofing material on it. Only after this is it possible to install FBS blocks. For horizontal waterproofing of a foundation mounted on a compacted crushed stone-sand base, a special “pouring” of heated bitumen is used.

Reliably protect the foundation when high level groundwater will be made possible by the additional construction of a drainage system around the perimeter of the building under construction, and to divert rainwater a blind area will help.

If the house design includes basement, then horizontal waterproofing must be done below the level of the basement floor (at its junction with the foundation wall). In this case, the following work must be done:

• pour a layer of clay onto the leveled bottom of the pit and compact it well;
• pour a concrete pad;
• after the concrete has set, but not earlier than 10 days, apply a layer of bitumen mastic over the entire plane of the hardened surface, laying overlapping roofing material on top;
• Coat the surface with bitumen again and lay roofing felt. This will maximize the protection of the future basement floor from moisture penetration from the ground;
• install FBS blocks on the prepared surface according to the project;
• Fill the floor with a layer of concrete and level it, performing the final work as with a regular screed.

After completion of construction strip foundation, horizontal waterproofing is also installed along its upper level. To do this, FBS blocks are covered several times with a layer of bitumen, on which heated roofing material is laid. The lower and upper edges of the rolled material extending beyond the structure are placed under subsequently installed vertical waterproofing in order to form a unified protection of the foundation from moisture penetration.

Basic methods of vertical waterproofing

Before applying a waterproofing layer to the constructed structure, the surface of the FBS blocks must be prepared in a certain way - cleaned of dirt, gotten rid of protrusions, leveled with a cement-sand mixture. It is necessary to carefully repair chips and cracks, and the seams of the block masonry should be treated with a cement-polymer composition.

Depending on the materials used for vertical waterproofing, there are several main methods of its construction:

• plastering – based on cement compositions;
• coating or spraying - using mixtures based on bitumen or polymer;
• adhesive – using rolled materials.

Each method has its own advantages and disadvantages, and they are used depending on ground conditions construction sites. In particular, one of the determining factors is the groundwater level.

Plaster applied to foundation walls simultaneously performs two functions. In addition to sealing cracks and seams between blocks, it waterproofs the underground structure to some extent, which is a definite advantage. But plaster protection is used only if the groundwater level is below the foundation level.

In addition to cement, the mixture contains liquid glass, sodium aluminate and other additives. Ready solution applied with a spatula to the pre-installed one using dowels plaster mesh, which improves the retention of the applied layer on the foundation walls.

The main disadvantage of plastering is the low hydraulic stability of the cement layer, which contributes to the appearance of cracks in it.

Coating and sprayed waterproofing

It is the most common method used to protect underground structures from groundwater, the level of which rises above the base of the foundation. The insulating materials used here are wide range ready-made bitumen mastics. The availability and low cost of the ingredients that make up the mixture allows you to independently make a simple coating mastic from:

• construction bitumen;
• used machine oil.

Cheap technical oil acts as a plasticizer, preventing molten bitumen from quickly hardening. When processing FBS blocks, the mastic penetrates into all cracks and gaps, preventing further moisture from penetrating inside the foundation walls. The surfaces are coated with the heated mixture in several layers. The disadvantages of using traditional bitumen mastic are its mediocre water resistance, weak adhesion and the fragility of the layer.

Cooling and reheating of bitumen is not allowed, as this leads to a partial loss of its waterproofing properties.

As a more reliable and high-quality alternative, it is recommended to use liquid polymer mastics on a bitumen or cement-sand base, purchased at construction stores. They have increased moisture resistance due to the additional introduction of hydrophobic synthetic additives into the composition. Such mastics do not require heating, and the number of applied layers can be reduced to two. Their only disadvantage is their high cost.

One of polymer materials, allowing for highly reliable waterproofing layer, considered liquid rubber. It is applied using a sprayer, deeply filling pores and cracks. Also, one- and two-component compositions are used in the work, spread on the surface to be treated with a brush or brush.

This method is considered quite effective, as it is used as an additional method when waterproofing FBS blocks with liquid bitumen. The block foundation is covered with roll or film materials on a surface pre-treated with mastic. It should be noted that the once widely used roofing felt and roofing felt are gradually being replaced by more progressive waterproofing materials made on the basis of fiberglass. It has a double-sided coating of modified bitumen with additional protection in the form of a polymer film.

Heated with a burner roll material, is overlapped on the bitumen layer, with an overlap of 10-15 cm. To avoid the formation of air inclusions, the surface of the waterproofing layer is rolled with a roller.

In order for any building to be durable, it is necessary to pay due attention proper arrangement its main load-bearing part is the foundation. To do this, you should not only choose a durable material that can withstand the weight of the superstructure for years, but also, if necessary, protect the base of the building from destructive influences. The main factor that can adversely affect the strength of a material located below ground level is moisture. This is why waterproofing foundations made of blocks, slabs and even monolithic reinforced concrete is sometimes necessary. In what cases is it necessary to create a moisture barrier, and what options for its arrangement exist today? This will be discussed further.

Main types of foundations and materials for their arrangement

There are several types of basic structures for buildings. Which one to choose in a particular case is determined based on several factors:

• soil type;
• level of surface groundwater;
• presence/absence of a basement in the project.

The main types of foundations are as follows:

• tape (recessed and non-recessed);
• pile;
• pile-screw;
• slab;
• blocky.

Now let's figure out what type of foundation is suitable in some options.

For one-story buildings without a basement, made of any building materials, when stable soil layers are located at a shallow depth, a shallow foundation is sufficient. It can be made of concrete, having first created a reinforced frame, or made of moisture-resistant rocks, which are poured in layers cement-sand mortar.

If you plan to have a basement, you need to make a recessed foundation. The material used is concrete, for pouring which a removable formwork is created, or FBS blocks.

If the building site has unstable heaving soils, it is recommended to slab foundation. It is a monolithic slab of a certain thickness that is poured under the entire area of ​​​​the future building. This significantly increases the support area, giving solid foundation for the add-on.

In the case when heaving soil combined with groundwater lying close to the surface, it is better to use piles, or their combination with a non-buried strip foundation. Piles can be filled with concrete with its reinforcement, after drilling wells, or use ready-made screw supports. Depending on the type of foundation, as well as the presence or absence of a basement, the need for its waterproofing and its degree is determined.

Which foundations need to be protected from moisture?

High quality concrete, natural stone, used to fill the building base, FBS blocks, while in the ground, are not destroyed by moisture. Therefore, non-buried foundations do not need waterproofing. Protection from moisture is necessary only in cases where a basement is provided, in which a garage, workshop, storage for crop products or any other room can be located. functional purpose. After all, the inner foundation surface with this option is the basement wall.

The slab base also needs to be created as a moisture barrier, since the foundation slab lies almost on the surface of the soil, so if there is an excess of moisture in the latter, it will soak into the room. Sometimes concrete piles also protect from moisture. This is done during their installation. First, a moisture-proof case is placed in the drilled wells, a reinforcement cage is inserted, and only then concrete is poured.

What are buried foundations made of?

Until recently, the main material for creating a buried foundation was concrete, which was poured into a previously created removable vertical formwork. Such a foundation requires the creation of an external waterproofing barrier, since moisture is saturated even through a monolithic structure if there is excess moisture in the soil.

Important! Now, when creating a recessed strip foundation, you can use permanent formwork, made of durable polystyrene foam. In this case, waterproofing is not needed, since this polymer has hydrophobic properties.

The second material that is used for arranging buried foundations is FBS blocks, which are concrete structures a certain shape and size, from which the foundation is built like brick wall. The peculiarity of the FBS base is that the seams between the concrete fragments are filled with ordinary masonry cement-sand mortar or assembly adhesive, are much more moisture permeable than the FBS concrete body. Therefore, a block foundation requires more careful waterproofing when compared with a monolithic poured foundation.

Important! The foundation made by the FSB has one more feature. The point is that blocks have standard size, therefore it is not always possible to accurately fit them to the planned perimeter. Places where a whole FBS does not fit have to be filled brickwork. These areas require multi-layer waterproofing protection.

Methods for waterproofing buried foundations

The moisture protection of a structure made as a monolith is not fundamentally different from the waterproofing of a block base. The only difference is that in the case of FBS, you should first additionally insulate the seams between the blocks, and then proceed in the same way as in the case with monolithic concrete. To protect the seams, special hydrophobic plaster is usually used. Then one of the following options is applied:

• bitumen-based materials;
• liquid rubber;
• impregnating waterproofing;
• water-repellent plaster.

Let's consider each method of waterproofing in more detail.

Bituminous materials

The most commonly used material for waterproofing concrete bases is bitumen mastic. It is relatively inexpensive, easy to apply and creates a continuous hydrophobic layer. This material must be applied to a dry surface, so after pouring the concrete foundation structure you need to wait for it to dry. The mastic is applied to the surface in a heated state using a stiff brush. If you want to apply a second layer, you need to wait until the first one dries completely. The disadvantage of the material is that it is destroyed at low temperatures, so in the northern regions it quickly cracks and loses its waterproofing ability.

Liquid rubber

This material appeared quite recently. It is applied to the surface by spraying, for which special equipment is used. Liquid rubber, depending on the need, is applied in one or two layers. The material works well in any range of possible atmospheric temperatures and has a long service life. However, liquid rubber is not an inexpensive means of moisture protection, nor is the equipment for working with it.

Impregnating waterproofing

This technology also appeared recently. Its essence is that concrete is impregnated to a depth of 20 cm special means. As a result concrete surface becomes waterproof. Manufacturers of penetrating waterproofing agents promise an almost unlimited period of action of the substance. Such moisture-proof treatment of foundations is carried out by specialized teams that provide relevant services. Such products are applied in compliance with a certain technological sequence using special equipment.

Water-repellent plaster

This method of waterproofing is unlikely to effectively protect against suitable groundwater. It is used where water protection from natural soil moisture is expected, which is a consequence of precipitation. Plaster mixture made on a cement base with the addition of water-repellent polymer additives. It is used both for processing seams between FBS and for creating a continuous waterproofing coating external foundation surface. The material is relatively inexpensive, is applied like any other plaster, and in conditions of moderate soil moisture shows a good hydrophobic result.