How to make foundation insulation. Foundation waterproofing horizontal

To pour or not to pour, that is the question! This is how one well-known saying can be paraphrased when a forum member undertakes to fill in a tape without using a removable formwork.

Pouring a strip foundation into the ground

In a heated debate about whether it is possible to pour a strip foundation into the ground or whether it needs formwork, many copies have been broken. But it's better to see once than hear a hundred times . Our forum member with a nickname Radomir999 after much deliberation and reading the recommendations of users, FORUMHOUSE decided to build a private house from warm ceramics with a strip foundation of the building directly into the ground. And, as subsequent events showed, he never regretted it!

Radomir999:

- Having studied the information on our forum, initially I chose this method of building this type of foundation. We will pour the tape for 1 time with factory-made concrete of the M250 brand, in a wooden formwork. Next, a strip foundation will be carried out in the ground (bituminous coating + fusing of glass isol).

In the opinion of the members of the forum, correctly, according to technology, delivered and then removed will always remain a “business” board. And in the future it will be possible to put it on the subfloor or roof sheathing.

But the father of our forum member did not want to spend money (about 50-60 thousand rubles) on formwork from boards 40-50 mm thick.

Radomir999:

- Together with my father, we walked around the neighbors in the settlement, asked about the types of foundations. It turned out that everyone is pouring concrete without formwork at all! Polls are practiced pouring tape into a trench, and houses have been standing for 5-10 years.

The forum member decided to make a fixed formwork from XPS in the ground. And from above, above the ground, I planned the installation of a low formwork from boards for the basement.

However, difficulties arose at this stage.

Radomir999:

- I started looking for topics about how to pour tape on the surface of the earth, but I didn’t find anything sensible. Everyone categorically advised to build high-quality wooden formwork. It was also suggested, as an option, to pour concrete in layers (for 2-3 times): when the previous layer hardens, disassemble the formwork, raise these boards up for the next layer, and so on to the top of the foundation. But this option did not suit me either.

Because pouring concrete under the tape at a time is the best solution of all.

We already have one on our forum. She helped our forum member draw up a detailed plan for the construction of a strip foundation. After all, careful planning is already half the success of the whole business.

Radomir999:

– Topikstarter this topic came up with a good option. It was here that I saw the first drawings and options for casting a strip foundation into the ground in 2 versions: with roofing felt and with foam plastic.

But, according to our user, roofing felt in the ground at the base of the foundation tape would still not be an ideal option, because. the walls of the strip foundation would not turn out to be even. Therefore, he leaned towards extruded polystyrene foam, despite the fact that it is 2.5 to 3 times more expensive than regular foam.

Radomir999:

– Comparing the prices of XPS with the prices of formwork with a height of 1.9 m from boards with a thickness of 50 mm, my father and I found out that XPS will cost us less.

Also, when using EPPS, the walls of the strip foundation will be smooth and will not cling to the ground in the spring when heaving. And the foundation will be immediately insulated.

Having carefully considered all the details regarding the construction of the strip foundation, Radomir999 came up with the following building plan:

Pouring concrete without formwork

1. Dig a trench by hand.

The walls of the ditch will have maximum smoothness and will be even for easy installation of XPS sheets in the ground.

2. Lay sand 20 cm at the bottom of the trench. Pre-moisten the sand, and then ram it.

So we level the bottom of the pit.

3. Lay a 200 micron polyethylene film in the trench. Glue the joints of the film with adhesive tape.

4. On top of the polyethylene, lay roofing material on the bottom of the trench, also at the overlap joints.

5. Then vertically insert sheets of XPS 50 mm thick and drive them into the ground with nails.

6. Reinforce the tape.

7. Install formwork from boards 15 cm wide, 25 mm thick, above the ground - for the basement of the foundation.

8. Insert XPS sheets horizontally inside the wooden formwork, fastening with self-tapping screws from the outside.

The dimensions of the XPS sheets are 120 cm x 60 cm x 5 cm. Therefore, it is easy to place the first row in the ground vertically, and the second and upper row horizontally.

From our article you will learn how to

Radomir999:

- For clarity, the dimensions of the perimeter of my strip foundation are as follows: 11.6 x 11.6 m, there is an average load-bearing wall. Height 180 cm (130 in the ground, 50 above the ground - basement), tape width 50 cm. The depth of soil freezing is 1.6 m. Groundwater does not disturb, there is a perch in the spring.

Pouring the strip foundation into the ground: according to step instruction

1. Foundation tape marking

Radomir999:

- To mark the walls of the trench, you will need: strong threads, a tape measure longer than the diagonal of the perimeter of the house, a plumb line; long self-tapping screws with a large noticeable hat.

Then the place on the site is determined where you want to dig a trench. Install 2 boards at the corners. Then small nails are hammered into them, to which ropes are tied. Sticks are hammered into the ground with the removal of the corners so that they do not interfere with your further digging.

For accuracy of measurements, calculate what the diagonal of your perimeter is according to the Pythagorean theorem. Then, with a plumb line, mark several points on the ground of the line you need. And stick the screws under the stretched rope with the removal around the corner, not far from the board.

2. trench digging

Radomir999:

– Father himself dug two walls under the strip foundation in two weeks the buildings . The trench walls turned out to be good. The difference is especially noticeable compared to the walls where the tractor was digging.

Also, as in the construction of the basement, the tractor should not dig a little to the bottom of the trench, so as not to disturb the parent soil. And you can follow the depth of the structure on the board, on which you first need to make a mark on the depth of your trench and, lowering it, check the depth of the dig.

The trench must be made wider than the thickness of the foundation + EPS by 5 cm.

Radomir999:

- After the tractor digs a trench, I advise using a hydraulic level, starting from the lowest corner of the perimeter, determine the "zero" at all other corners. At these points, you will screw in the self-tapping screw and pull the ropes. This will help you level the bottom of the trench.

Sand for laying on the bottom of the trench Radomir999 advises moistening on the street and laying it on the bottom of the trench already moistened. This is necessary in order to prevent thinner and moisture from appearing at the bottom of the trench.

After that, you can ram it with a vibrating plate.

Radomir999:

– We didn’t have a vibrating plate, we rammed a pre-sawn oak chock with my father. We have a sand cushion of 20 cm.

By and large, the pillow is harmful, and if you have an ideal bottom and corners in terms of level, then professionals advise you to do without it.

3. We line polyethylene in the trench

A sufficient thickness of polyethylene for this purpose is 150 microns, but Radomir999 laid 200 microdistrict:

- If possible, it is better to take a roll with a larger width so as not to glue the joints with tape. If you're going to tape it, be sure to tape it on both sides! We glued with one, internal, and this was our mistake.

Condensation flows under the polyethylene in the heat. If the joints are assembled so that the condensate enters the pocket, then in these places the adhesive tape will peel off and condensate with dirt will flow. Polyethylene also maintains moisture in the trench and on hot, sultry summer days, the walls of the trench do not dry out. If they dry out, they begin to crumble, crumble, there are large cracks and the wall may collapse.

4. We line the roofing material to the bottom, like a trough.

It is important to remember that you should not leave the rolls in the heat, because. the bitumen will stick together, this will affect its quality and the roll will be difficult to open.

5. Installing XPS sheets.

We put the sheets vertically in level, joining their groove into the groove. Then we nail them to the ground with nails 20 to 30 cm long (depending on the unevenness of the trench walls).

Radomir999:

– For nails of 20 cm, we used washers. One sheet took 6 nails. At the corners, you can fix it with corners (home-made) with bolts and nuts.

After installing the bottom row of EPS, backfilling with sand can be applied. Radomir999 advises not to save on sand.

This is not correct according to SNiPs, and if it rains and water gets behind the XPS sheets, the clay will swell and squeeze out the sheets.

Force majeure

Despite the detailed plan, nature has made its own adjustments. Instead of the promised Indian summer from Moscow to Cheboksary, where our hero lives, there were prolonged heavy rains. This could lead to the collapse of the walls of the trench. And the carefully leveled bottom, before the eyes of the forum member, gradually turned into a viscous slurry, on which the foundation cannot be poured. It was necessary to urgently come up with something in order to save the fruits of their labors in any way!

Radomir999:

- It rained, and water sometimes got inside the trench, in addition, the roofing material began to crumple. On the polyethylene with which we decided to cover the trench, puddles of water began to collect, into which worms fell. Birds sat down to peck at them and tore polyethylene with their beaks. We glued the torn places with adhesive tape, but water seeped through the adhesive tape in some places. Therefore, we decided to pour a concrete pad 10 cm thick at the bottom of the trench.

6. Foundation reinforcement

When reinforcing, it is necessary to remember the main points of SNiPs:

1) The protective layer of concrete must be at least 5 cm.

This means that the reinforcement should not fit closely to the walls of the trench. On the sides of the trench and on top, the reinforcement should recede from the edge of the strip foundation by 5 cm. From the bottom - 7 cm. In the absence of a concrete cushion and at least 3.5 cm if there is one.

2) When the height of the MZLF (shallow foundation) is more than 70 cm, it is necessary to lay not only the lower and upper rows of longitudinal reinforcement, but also the middle rows, which do not carry loads, but are constructive.

It is enough to make the middle rows of longitudinal reinforcement from reinforcement d = 12 mm. If the wall is more than 3 m in length, then only along the side faces of the strip foundation. That is, for the middle rows of the longitudinal, 2 rods from the 12th reinforcement are sufficient.

3) To anchor the reinforcement in the adjacent adjoining wall, its ends must be bent or additional L-shaped corners should be used to strengthen the anchoring.

7. Plinth formwork

Radomir999:

- At the forum, it is advised to install formwork from boards with a thickness of 40-50 mm. Experts recommend such boards for everyone: for those who make the entire height of the strip foundation of 1.5-2 meters, and for those who, like me, carry out "formwork work" t Only for the base, i.e. for the above-ground part of the foundation. We took the 25-ku and never regretted it. The main thing is to put in the structure more often supporting triangles and crossbars. Ours was 1 meter apart. The height of the formwork is preferably 5 cm (at least) above the edge of the foundation so that the concrete does not splash.

8. We install the top row of EPPS inside the formwork

9. Installing sleeves in a trench for future sewer and water pipes

Radomir999:

- We bought a plastic red pipe with a diameter of 200 mm and a length of 1 meter. There are 2 sleeves from it, where the sewerage will pass.

Need to think ahead : how and where the sewerage will run, under what slope the pipes will go, what adapters will be installed.

And here are some secrets:

• The sleeves must be 2 times wider than the sewer pipes;
• Pipes from the kitchen, shower, bathroom d = 50 mm are laid with a slope of not more than 3 cm per 1 meter of pipe;
• Pipes from the toilet bowl and the outlet pipe to the septic tank d = 110 mm are laid with a slope of not more than 2 cm per 1 meter of pipe;
• Make all transitions from horizontal to vertical with corners of 2x45 degrees or 3x30 degrees;
• The sewer pipe should go straight to the septic tank.

10. Pouring concrete

Radomir999:

- We poured a solution of concrete grade M250, 48 cubic meters. By this time, the rains had so washed away the ground around the trench that, even while working in galoshes and boots, we were bogged down in the mud. We could forget about the mixers loaded with concrete that will drive up to our trench, we had to go the hard way and order a concrete pump.

When pouring concrete with a concrete pump Radomir999 advises:

1. In advance, in writing, agree with the concrete supplier on the continuous delivery of concrete;

This will help to collect a penalty from the concrete supplier company if the mixers are late.

2. It is required to buy for all builders who will be near the concrete pump supply pipe: safety glasses, cheap disposable surgical bandages, rubber gloves;

Radomir999:

- The jet of concrete is so strong that splashes of the concrete mixture fly into the eyes, mouth, hands dry, fingernails hurt.

3. Putting the concrete pump truck with its back to the approaching mixers will speed up the work.

Radomir999:

- Because cold weather began, we decided to play it safe and ordered an anti-frost additive for concrete. As taught on the forum, I ordered 49 cubic meters, that is, my calculated volume + 1 m3 in reserve, in case of force majeure. As a result, exactly 48 cubic meters were poured, and after pouring, a small area in front of the house was concreted from the remains. Here you have a ready-made platform for the entrance of the car!

FORUMHOUSE users can find out all the details and features, read a detailed and visual story of our forum member about how he is. And our video talks in detail about how to build a basement in conditions of high groundwater.

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 the territories of our country. By itself, water is not particularly terrible for concrete, on the contrary, in a slightly moistened state, concrete continues to gain its strength over the years. However, there are three big BUTs.

Firstly, concrete has such a property as capillarity. This is the rise of water up the smallest pores inside the material. The simplest example of this phenomenon is the wetting of 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 an increase in heat loss, the appearance of fungi and mold, damage to interior finishing materials.

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

Thirdly, we do not live in the tropics, and sub-zero temperatures for our climate in winter are the norm. As everyone knows, when water freezes, it turns into ice, increasing in volume. And if this water is in the thickness of 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 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 done, and will be discussed in this article.

By and large, protecting the foundation from moisture can be done in two ways:

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

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

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

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

The use of a waterproofing coating is available to everyone and, with certain skills, you can even do it yourself.

Foundation waterproofing materials.

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

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

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

I) Coating waterproofing is a material based on bitumen, which is applied to the surface (often in 2-3 layers) with a brush, roller or spatula. Such coatings are commonly referred to as bituminous mastics. They can be made independently or purchased 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 melts), pour it into a metal container and put it on fire until completely melted. Then remove the bucket from the fire and add used oil to it, and preferably diesel fuel (20-30% of the mastic volume), mix everything thoroughly with a wooden stick. How this is done is shown in the following video:

Ready-made bituminous 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 reported in the instructions on the label. There are several manufacturers of such mastics with different prices and different characteristics of the finished coating. The main thing when buying them is not to make a mistake and not to take material, for example, for roofing or something else.

Before applying bituminous mastic, it is recommended that the concrete surface be cleaned of dirt and primed. The primer is made with a special composition, the so-called bituminous primer. It is also sold in stores and has a more liquid consistency than mastic. Coating waterproofing is applied in several layers, each of which - after solidification of the previous one. The total thickness of the coating reaches 5 mm.

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

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

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

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

Such materials are more expensive, but also much better and more durable. There are two ways to work with rolled waterproofing - gluing and fusing. Gluing is carried out on a surface previously primed with a bituminous primer using various bituminous mastics. Welding 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 the foundation waterproofing compared, for example, with coating materials. They are also quite affordable and affordable. The disadvantages include the complexity of the work. It is quite difficult for an inexperienced person to do everything qualitatively. Also, do not cope with the work alone.

The appearance of self-adhesive materials on the markets a few years ago made it much easier to work with rolled 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 through the pores into its thickness by 10-20 cm and crystallize inside, thereby clogging the passages for moisture. In addition, the frost resistance of concrete and its protection from chemically aggressive groundwater are increased.

These compositions (Penetron, Hydrotex, Aquatron, etc.) are quite expensive and have not been widely used 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 in other ways.

For more information about the properties of penetrating materials and their correct application, see the following video:

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

The advantage of this technology is the simplicity and speed of applying materials. The downside is the low durability of the waterproofing layer and less water resistance compared to the materials described above. The use of waterproofing plasters is more appropriate for leveling the surfaces of foundations or, for example, for sealing joints in foundations made of FBS blocks, before their subsequent coating with bituminous or rolled waterproofing.

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

How to choose waterproofing for the foundation?

As you can see, there are currently a huge number of all kinds of waterproofing materials for protecting 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:

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

A different combination of these three factors determines which waterproofing should be preferred in this case. Consider the most common options:

1) Column foundations.

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

The cheapest option is to use a regular roofing felt. If it is sprinkled, it is better to roll it with the smooth side outward, so that in winter, when it freezes, less soil sticks to it. It is advisable to make sure that the thickness of the waterproofing around the entire circumference is at least two layers.

When using asbestos or metal pipes for a columnar foundation, they can be pre-coated with any coated bitumen waterproofing in at least 2 layers.

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

2) Shallow strip foundations (MZLF).

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

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

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

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

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

Also, do not forget about the cut-off waterproofing layer above the level of the blind area.

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

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

If the foundation is made up 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.

In order not to damage the waterproofing layer during subsequent work, try to walk on it as little as possible, and immediately after installation, close it with extruded polystyrene foam.

At the end of the article, we pay attention to two more points. Firstly, when the groundwater level rises above the level of the basement floor, drainage must be done (a system of drainage pipes laid around the perimeter of the house and wells for revision and pumping out water). This is a big topic, which will be discussed in a separate article.

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

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

Most builders prefer the first method, because. it allows you to immediately "kill two birds with one stone." EPPS and protects the waterproofing and insulates the foundation. Read more about insulation of foundations

Due to its performance, simplicity of design and durability.

Unlike other types of foundation, the tape type is able to work on most types of soil and allows the construction of several constructive options using different building materials.

The main problem with strip foundations is in contact with the ground along the entire length of the strip.

There is a possibility of concrete getting wet, requiring measures to isolate the material.

Any type of strip foundation either consists completely, or includes concrete in its composition. This material has a high ability to absorb water.

When the temperature drops below zero, it freezes, increases in volume and destroys the foundation, as if exploding it from the inside. The only way to prevent this situation is to waterproof the tape, install a waterproof cut-off that prevents moisture from penetrating into the thickness of the material.

If this procedure is neglected, the service life of the base is significantly reduced, and the building, installed on a problem base, will be at risk of subsidence, destruction, or other undesirable processes.

In addition, a wet base will become a source of water penetration into the wall material, causing destruction, corrosion of metal parts and other dangerous and undesirable processes.

Specialists treat waterproofing very responsibly, considering it one of the most important procedures.

Differences between a shallow and ordinary foundation

There is no fundamental difference in the installation of insulation. The difference is only in the area of ​​application of the compositions, the amount of material and the duration of the process.. The device of the strip foundation differs from the usual type only in the depth of immersion, therefore all technological methods are the same.

However, the difference in immersion of the concrete base creates a significant difference in the density of contacts between concrete and soil moisture. The usual type of strip foundation is immersed below the freezing level of the soil.

The base is in more risky conditions, changes in the level of soil water or the influx of rain, melt moisture create a noticeable threat to the material. Therefore, for conventional types of strip foundation, the installation of waterproofing requires greater care and quality of application.

What materials should be used

Foundation waterproofing can be implemented in various forms.:

• Roll pasting materials. Represent various membranes, films or bitumen dense (roofing material, glassine, hydroisol). Applied by sticking to a layer of mastic or using heat.
• Coating materials. These include bitumen (heating and application), cold mastics (sold in a ready-to-use form, applied by coating surfaces with a continuous layer).
• penetrating materials. Materials that can be absorbed into the thickness of concrete and crystallize inside, filling the pores of the material and preventing the penetration of moisture. Apply by brush or spray.
• injection materials. They have an effect similar to penetrating compounds, but are applied by drilling wells and pumping material into them under pressure. As a result, the composition impregnates a larger volume of concrete, strengthening it from the inside.
• Painting materials. These include liquid rubber or liquid polyurethane foam, which, after application, harden into an elastic water-repellent film. The application is simple, but in terms of strength, these materials are inferior to roll types. The service life of painting materials is relatively low, which limits the use of this type of waterproofing.

The main methods of horizontal waterproofing

Horizontal waterproofing in the ground, as the name implies, is installed on surfaces located in a horizontal plane.

With regard to the strip foundation, this is the underlying layer of insulation, installed on a sand and gravel cushion (usually a layer of roofing material), as well as a layer laid on top of the tape and designed to cut off the capillary absorption of moisture by the wall material.

There are two types of horizontal waterproofing:

• Coating. Mastics or similar materials are used, applied to the surface with a brush or roller.
• Okleyechnaya. Rolled waterproofing materials are used.

The first option is only suitable for the upper cut-off layer applied to the surface of the tape. The second option can be used both from below and from above.

In addition, according to the type of action, different types of waterproofing are used:

• Antifiltration. Provides a hermetic cut-off from moisture penetration.
• Anticorrosive. Designed to protect materials from the aggressive effects of chemical compounds present in soil water or formed as a result of soil contact with rain, melt or ground moisture.

Horizontal waterproofing is considered more important and responsible, since it cuts off the effect of moisture coming from below, excludes the capillary flow of water into the array. The most important element is the lower (underlying) layer of roofing material, which is laid in front of.

The insulator is spread in a layer at least 10 cm wider on each side than the future tape. Subsequently, the edges of the roofing material are raised and glued to the concrete with bituminous mastic, forming a kind of wrapping.

Vertical waterproofing methods

Vertical waterproofing is installed on the walls of the concrete tape both from the outside and from the inside. The procedure is designed to protect the foundation from moisture, which results in the formation of mold, fungus, destruction of concrete, frost breaks in the array in winter.

The most critical area is the outer side of the tape, but it is also necessary to install protection from the inside. This is necessary to prevent penetration into the condensate formed on the cold surface of the foundation tape.

If available, then the installation of waterproofing becomes a mandatory measure that accompanies the organization of high-quality ventilation.

The choice of material for vertical waterproofing must be made carefully and responsibly. After backfilling the sinuses, access to the surface stops, so everything must be done without errors.

For application on concrete tape are used:

• Coating compositions (mastic, heated bitumen). It is recommended only for application from the outside of the tape, as they are effective only with direct moisture pressure. The application is carried out by spraying, painting or (most often) coating surfaces. It is most convenient to use ready-to-use mastic, since you have to use an open fire to heat the bitumen, which is not always possible.
• Roll materials. Traditional type of waterproofing, along with tar. The most common type is roofing material; glassine and hydroisol are also common. Drawing is made either on a layer of hot bitumen, or on mastic. The installation of the second layer can be carried out on the previous one by heating the material itself, the molten layer of bitumen connects the layers like an adhesive composition.
• penetrating compounds. This type of waterproofing impregnation appeared relatively recently, but managed to establish itself on the positive side. The compositions do not form a water-protective cut-off, but change the properties of concrete, stopping the possibility of absorbing moisture. There are compositions for surface application and for deep impregnation from the inside by pumping the composition into drilled holes. After application, the composition impregnates the base material, crystallizes, clogging all the capillaries of the concrete and blocking the possibility of absorption.

When choosing the most suitable material, one should take into account the operating conditions of the foundation, the hydrogeological composition of the soil, the type of foundation, and. Experts recommend the use of penetrating compounds that allow you to obtain high-quality waterproofing of a new type.

NOTE!

When applying penetrating waterproofing compounds, it is necessary to ensure proper conditions (dry surface, temperature not lower than zero, no scorching rays of the sun or strong wind), and also follow the technology of use.

Pile-strip foundation

Do-it-yourself waterproofing of the base consists of two stages - processing the piles themselves and applying insulation to the tape. For waterproofing piles, appropriate techniques are used, due to their type and method of immersion in the ground.

For example, bored piles are poured into tubes made of a moisture-impervious material. Driven piles are isolated in accessible areas. Modern types of concrete piles are made of concrete with hydrophobic additives, which exclude the penetration of moisture into the array.

The tape is processed with one of the most affordable or suitable insulators for the construction conditions.

Both traditional methods can be used - coating with hot tar, bitumen, pasting with roofing material, etc., as well as more modern methods of impregnation or spraying of rubber-bitumen liquid emulsion or polyurethane foam.

The final choice is dictated by a combination of various factors and can only be made on the basis of an examination of a particular foundation.

Which of the methods is the best?

Among the most optimal methods of waterproofing include the impregnation of concrete with hydrophobic compounds. Unlike traditional options, which are laborious and do not provide complete tightness, impregnation does not create an outer layer.

When backfilling or otherwise working with the surface, the cut-off is easily damaged, which will create the possibility of moisture penetrating into the hole. Impregnation eliminates this danger by compacting and clogging the concrete to a certain depth.

Mechanical influences, contact with objects, loads during backfilling of the sinuses will not be able to damage the resulting protection, the base will not lose its hydrophobic qualities.

Useful video

In this video you will learn how to waterproof the foundation:

Conclusion

Contacts of the concrete base with moisture must be excluded by all available means. The application of the insulator must be done with all care and accuracy, avoiding gaps or cracks.

It must be remembered that the repeated possibility of applying the composition may not happen, and the durability of the entire building largely depends on the reliability of the concrete tape. Do not rush or try to shorten the surface treatment time, this can increase the service life for many years.

In contact with

Do-it-yourself waterproofing of a strip foundation includes the protection of vertical parts and a horizontal surface at the basement level. The side parts are coated with bitumen if there is contact with the ground.

This type of foundation is perhaps the most common building load-bearing structure for residential buildings, because the construction work for its construction is quite simple. Do-it-yourself waterproofing of a strip foundation includes the protection of vertical parts and a horizontal surface at the basement level. The side parts are coated with bitumen if there is contact with the ground.

It should be noted that the consumption of materials for waterproofing work on a strip foundation is quite moderate, which makes such a supporting building structure optimal in terms of price, quality and construction time.

One of the main criteria in the calculation of the strip foundation is the composition of the base soil and the level of groundwater. In addition to dimensional calculations, frame reinforcement schemes and concrete grades, these parameters are also important to take into account when waterproofing a finished structure, as this will largely determine its durability and load-bearing capacity.

Features of insulation work on a strip foundation

Scheme of the horizontal waterproofing tape device

Those who are faced with the construction of their house for the first time and decided to build it on a strip shallow foundation should remember an important point - waterproofing the strip foundation is a must! This rule cannot be neglected even in cases where the building will be located on rocky soils in the absence of a groundwater level in the freezing zone of the earth. In addition to waterproofing and warming the foundation itself, it is highly desirable to make a blind area.

Waterproofing strip foundation consists of the following steps:

1. Insulation work carried out at the stage of excavation. These works include the installation of a horizontal layer of roofing material under the foundation cushion. This protection is laid directly on the ground, drainage layer or coarse bedding, depending on the design design. The main task of this roofing material layer is to protect the foundation cushion from possible flooding or frost heaving of the soil. To prevent premature destruction of such a structure by precipitation, it should be protected with a blind area. A pillow under the foundation may not be necessary, the need for its presence is established by calculations or design work.
2. Horizontal waterproofing. This type of protection is applied to a concrete pad, in front of the tape monolith. It is necessary to protect the joint between two structural elements - the foundation cushion and the strip foundation itself. If horizontal insulation is not performed, then water that has entered such a joint, after freezing, can violate both the integrity of the entire structure and damage individual elements of the foundation. In addition to the protection device, between the tape and the pillow, horizontal waterproofing also includes the laying of roofing material between the upper surface of the foundation and the material of the walls being erected (for example, brickwork). The functional purpose of such protection is similar to that which is arranged between the pillow, the sole and the tape supporting structure.
3. vertical waterproofing. Such protection of the structure from moisture should be carried out both on the outer surface and on the inner one. This is the most important part of the insulation, it is its device that is needed to ensure the durability of the entire structure. Horizontal insulation can be performed both with rolled material, for example, roofing felt, and with a bitumen-based liquid binder, such as bituminous mastic. In addition to such insulation, the foundation must necessarily have a blind area, only a combination of these two elements can effectively resist moisture.

The need for protection

Schematic representation of the implementation of vertical and horizontal waterproofing with a sand cushion (sole) on the ground

For those who want to save money at certain stages or completely abandon measures to protect the foundation from moisture, it should be remembered that even after the insulation and decorative finishing of the horizontal part of the tape structure, the concrete will still continue to absorb moisture coming through the air.

This moisture will gradually destroy the concrete, since microorganisms and spores will penetrate with it, and the moisture itself may contain solutions of aggressive components, which will also affect the structure, which can first lead to microcracks, and then to chipping of the surface. .

For additional protection of the entire structure from precipitation and flood waters, a blind area is also needed - without it, the base under the pillow (sole) may be blurred, which will create an additional load on the load-bearing elements of the entire building. Also, the blind area will not allow moisture to penetrate into the soil when areas of stagnant water form near the house, and after this water is removed, the blind area will protect the soil from rapid drying and cracking. The blind area should be erected under a slope from the building, to ensure the flow of water. The junction of the blind area and the foundation also needs to be isolated.

The procedure for the installation of roll waterproofing

The use of roll material for vertical protection of the supporting structure

Before starting work, the concrete surface should be cleaned of dirt and dust, and protruding sharp elements should be removed so that they do not damage the material. Then you should mark and cut the roofing material.

To glue the material, it should be heated with a gas burner so that the binder becomes liquid on the surface to be glued, after which it can be glued.

During the application of the material, it should be immediately smoothed so that it correctly takes the form of the structure and fills all the voids, this procedure will also remove air bubbles. If it is not possible to lay a solid sheet in any area, then the joining should be done with an overlap, heating the edges on both sheets and pressing them tightly, only then they are soldered.

Insulation should be applied to a clean concrete surface and should not be treated with a bituminous binder prior to this unless they are products from the same manufacturer that are intended to be used in combination. Otherwise, the web material may not stick due to the difference in the chemical composition of the organic binder component.

The procedure for the installation of coating waterproofing

Processing of the base tape with mastic standing on a pile foundation (pile-tape)

For these purposes, an organic bituminous binder is used, most often bituminous mastic. Before applying to the surface, it must be made liquid, for which a special solvent or heating is used. Before starting work, you should carefully read the manufacturer's instructions, which also give recommendations for liquefaction. When the composition is ready, it is applied with a brush or roller in several layers, filling all the pores and voids.

It should be noted that, compared to rolled insulation, coating insulation is less durable, and it should be used only if there is no threat of flooding and a low level of groundwater. Before installing the blind area, an additional layer of coating should be applied, the blind area itself can also be covered with mastic, but only after the concrete mixture has completely dried.

An example of the construction and waterproofing of a prefabricated tape supporting structure

Here is a specific example of waterproofing a tape bearing structure without protecting the sole with bitumen:

The house was designed without a basement and basement. To the water about 145 meters. Soil clay-whole. A trench is dug 100 cm deep. A layer of crushed granite without sand (150-200 mm). A reinforced tape of four rods with a diameter of 12 mm is laid.
Next, a couple of rows of FBS blocks are laid, we get a prefabricated supporting structure
Armo-belt 40 by 20 is produced
Rolled with a bituminous primer and rubemast is laid
Next, 3 rows of red brick are laid, after which a waterproofing primer is applied from the top
We lay the first row of the gas silicate block

More information can be found in the video

Waterproofing the strip foundation of a residential building is necessary to prevent moisture from concrete and reinforcing elements included in the foundation structure from sedimentary and groundwater. Wet concrete provokes the destruction of the foundation when the frozen water expands in the capillaries of the concrete tape and leads to corrosion of steel reinforcement, reducing the strength properties of the base of the house. The owners of individual buildings are able to independently correctly perform the work on arranging the waterproofing of the foundation of their home, having certain knowledge in this area.

The destructive effect of moisture on the foundation of a building occurs when water interacts with the materials of the foundation structure. The porous structure of concrete, saturated with capillaries, contributes to the constant absorption of moisture from the environment and groundwater. In order to make the tape base of a residential building as protected as possible from a humid environment, it is necessary, in accordance with (formerly SNiP 2.03.11-85), to ensure its hydroprotection by methods of primary and secondary corrosion protection (clauses 4.5, 4.6 and 4.7). Foundation waterproofing belongs to the category of secondary protection, based on the use of protective coatings or treatment with special compounds.

Scheme of waterproofing strip foundation.

Builders with their own hands or with the involvement of specialized organizations carry out activities for applying waterproofing materials to the foundation, taking into account external factors affecting the foundation of the house:

• Atmospheric precipitation and melt water;
• groundwater.

To guarantee the protection of the foundation from the penetration of sedimentary and melt water, it is enough to make a high-quality blind area around the perimeter of the entire building. To implement hydroprotection from ground moisture, it is necessary to take into account a set of initial data, among which the main ones are:

1. Type of groundwater near the building;
2. The depth of occurrence of groundwater passing near the construction;
3. Heterogeneity of soils in the construction area;
4. Purpose and planned operation of the house.

Let us consider how these factors influence the choice of the foundation waterproofing method.

groundwater type

Groundwater has a direct impact on the formation of the groundwater level (GWL) in the area of ​​the construction site and on the degree of soil moisture near the foundation. The diagram below shows the distribution pattern of the two main types of groundwater in soil:

• Verkhovodki are local foci of water formation that have a seasonal nature of existence. Verkhovodka lies near the earth's surface, is formed and exists only during high humidity of the environment, disappearing during dry periods;
• Groundwater lying near the surface of the earth and having a territorial regional distribution. The groundwater level is characterized by susceptibility to seasonal fluctuations.

As mentioned above, to protect against perched water, it is enough to make a good blind area and storm water. Protection from groundwater will depend on the depth of their occurrence. This dependency is discussed below.

Groundwater depth

“Recommendations for the design of waterproofing of underground parts of buildings and structures” of the Central Research Institute of Industrial Buildings, M., 1996 (amended in 2009), determined that the waterproofing of structures must be carried out above the maximum GWL by at least 0.5 m (p. 1.8 and 1.9). Since the average value of fluctuations in the level of HW in many regions of the Russian Federation, according to the results of geological surveys, is taken within 1.0 m, then in order to guarantee the protection of the foundation from ground moisture, it is recommended to adhere to this indicator as a reference point when choosing a waterproofing of the base of the building, depending on the depth of HW . In particular:

• At the groundwater level, less than 1 m below the base of the foundation, it is necessary to waterproof the foundation;
• If the GWL is deeper than the foundation by more than 1 m, the hydroprotection can be omitted.

It is necessary to take into account the possibility of increasing GWL as a result of infrastructure development in the region. As well as the maximum GWL for past seasons.

With a high level of GW exceeding the lower level of the foundation sole, in addition to waterproofing, it is necessary to additionally make local drainage to remove moisture from the foundation, as prescribed by "Design and installation of foundations and foundations of buildings and structures" (Chapter 11).

Soil heterogeneity

The heterogeneity of soils with different chemical composition leads to chemical aggression of groundwater in relation to concrete in the foundation, up to its destruction (concrete corrosion). The use of special corrosion-resistant concrete of the W4 grade is required when pouring the foundation and high-reliability hydraulic protection from materials resistant to aggressive environments.

Purpose and planned operation of the house

In the presence of basements equipped with their own hands for functional purposes such as a gym, workshop, etc. increased requirements are imposed on the reliability of waterproofing in order to prevent the deterioration of the microclimate in these rooms.

Properly equipped waterproofing of the strip foundation of a residential building requires compliance with three basic principles for constructing a waterproofing system for the foundations of buildings of any purpose:

1. Continuity of each waterproofing layer along the entire perimeter of the waterproofing;
2. Installing a waterproofing layer only on the side exposed to moisture, i.e. foundation waterproofing should be carried out outside, but in no case inside the basement;
3. Preliminary special preparation of the outer surface of the foundation for the subsequent application of waterproofing material.

Types of waterproofing strip foundation

According to clause 5.1.2 of the set of rules (formerly SNiP 2.03.11-85), waterproofing of the concrete structure is provided by:

• Lacquer and mastic coatings;
• Coating and plaster coatings;
• adhesive insulation;
• Impregnation of the surface layer of the structure or other surface treatment methods.

With regard to strip foundations, taking into account modern technologies for applying waterproofing, vertical waterproofing is divided according to the method of installation into the following types:

• Coating (painting);
• built-up;
• Plastering;
• Stick-on;
• injection;
• impregnating;
• Sprayable.

Coating (painting) waterproofing

Coating technology waterproofing is based on the use of bitumen and bitumen-polymer emulsions and mastics with the formation of waterproof films on the foundation surface.

Coating waterproofing protects the foundation from the penetration of capillary ground moisture in soils of low humidity when groundwater is removed 1.5-2 meters below the basement floor level. In the presence of hydrostatic head, it is allowed to use coating technology in the following versions:

• Bituminous mastic is used for pressure not higher than 2 m;
• Bitumen-polymer mastic - for a pressure of not more than 5 m.

Mastics are applied in 2-4 layers. The thickness of the coating hydroprotection depends on the depth of the strip base and is:

• 2 mm - for a base with a laying depth of up to 3 meters;
• 2-4 mm - for a foundation with a laying depth of 3 to 5 meters.

The advantages of coated bitumen protection are as follows:

• Relatively low cost;
• Lack of special requirements for the qualification of performers;
• High elasticity;
• Excellent adhesion.

Among the shortcomings, a short service life should be noted - already 6 years after the insulation loses its elasticity. The waterproofing layer is covered with cracks, which reduces the overall level of waterproofing. To increase the shelf life of the insulation, polymer additives are added to provide improved performance of the waterproofing coating.

The technology for applying mastic is simple. A special primer is applied to the previously prepared surface with a roller or brush, which ensures deep penetration into the foundation material. After the primer dries, bituminous mastic is applied in layers.

Fused and glued waterproofing

These technologies refer to the methods of waterproofing with rolled materials. They are used as independent measures for waterproofing, and as an addition to the do-it-yourself coating method. When using glued waterproofing, a traditional roofing material is used, which is fixed on the foundation surface treated with a bituminous primer.

With glued waterproofing, the thickness of the waterproofing layer reaches 5 mm. 2-3 layers are allowed.

Roofing felt can be fixed with special adhesive mastics in several layers with an overlap of 15-20 cm. Of modern materials, instead of roofing felt, rolled waterproofing materials are used - TechnoNIKOL, Technoelast and other materials for fusing on a polymer-based polyester, which increases the wear resistance of the coating. The service life of such waterproofing is 50 years.

Plaster waterproofing

Laying waterproofing with a plaster method is identical to do-it-yourself plastering of walls along lighthouses. For insulation, mixtures of moisture-resistant components such as polymer concrete and hydro concrete are used. The minimum thickness of the applied layer must be 20 mm.

The advantages of the plaster method include the cheapness of materials and ease of implementation.

Of the shortcomings, it should be noted:

• Average level of moisture resistance;
• Short service life, after 5 years cracks appear through which water can seep.

Injection waterproofing

The injection method of hydroprotection is based on pumping under pressure special polymer mixtures-injectors into the pores of the foundation. For injection technology, materials are produced on a mineral or polyurethane basis, which are close in density to ordinary water. If you use polyurethane-based compounds, then at least 1.5 liters will be required for waterproofing each square meter, while acrylic-based mixtures will require much less. Injection perforation is performed with conventional perforators or drills, the hole sizes (from 25 to 32 mm) are determined by the diameters of the injection packers and capsules. Upon completion of the injection process, the perforation is sealed with a cement-sand mixture of the usual composition.

Impregnation waterproofing

This technique is based on the impregnation of concrete with special organic binders that fill the concrete capillaries and form an antihygroscopic layer up to 30-40 mm deep in the concrete.

The technology of spraying a waterproofing material requires the use of a special spray gun. So far, the cost of materials is high, but their use is economically justified for waterproofing foundations of complex configuration, which are difficult to process in other ways.

Drainage as an auxiliary measure

The arrangement of drainage systems is designed to remove excess moisture from the foundation system of the building at a high level of groundwater. According to clause 11.1.15 of the set of rules, drainages are divided into general and local. Their use in combination with waterproofing allows you to protect the foundation from the penetrating effects of ground moisture.

Do-it-yourself waterproofing of a strip foundation is a complex technological process that requires a clear understanding of each stage of the entire event. Only in this case, a long period of trouble-free operation of the house will be ensured.

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