The connection of the blind area to the base of the snip. Blind area - device, technology and main stages of work

People who are far from the problems of construction often consider the blind area to be a convenient path around the house. My friend knows that nothing is done just like that. He is finishing construction country house and he is interested in the blind area with his own hands, step-by-step instructions on how to do it right. The question: why is this necessary, he asks me all the time.

Blind area of ​​the house

A blind area around the building, made with your own hands, protects the foundation

Vadik and I finished finishing the basement of his house. Until the coming rainy autumn you need to do the rest of the exterior work yourself. The first question he asked: what is a blind area and what are its functions?

Marking the width of the future trench around the house, I explained step by step instructions and purpose of the blind area:

  • the blind area protects the foundation from moisture and destruction;
  • she serves additional insulation perimeter buildings;
  • it is diverted from the base along it rainwater and the melting snow flows down;
  • since it is necessary, architects use it as an element of exterior design.

The blind area protects the foundation from moisture and destruction

Restoration of an old building begins with finishing the foundation and blind area. Without this, it is impossible to get rid of dampness not only in the basement, but also on the first floor. Insulating the top layer of soil around the perimeter reduces freezing of the soil near the foundation. A high-quality path around the house saves energy on heating, keeping the building warm. The work is not difficult and you can do it yourself.

Step-by-step instructions for creating a blind area with your own hands as an element of outdoor design

Blind area around the house

Designers use the blind area as an element of the composition. It emphasizes the line of the house, separating it from the lawns and yard. Constructed from the same material as the plinth finish, the walkway visually makes the building taller. The facade becomes complete. The structure seems more massive. There are step-by-step instructions on how to do everything yourself without paying for the work of specialists.
To create a unified ensemble of the house and the surrounding landscape, the same covering of paths around the yard and blind areas are used. Material and color are selected according to architectural style building. The tiles can be massive, natural, artificial stone. For wooden buildings choose a coating close to sand and natural tones. Avant-garde is emphasized by bright colors and non-standard forms. Strict glossy finishes and sharp corners suit techno.

Dimensions and slope of the path around the house, do it yourself

Vadik and I walked around the house, marking the roof line on the ground. The roof has a complex configuration and different size tilt and overhang. We chose the largest size and added 20 centimeters. We marked the width of the future blind area, which we will make with our own hands. The same size was laid off from the walls of the building at the corners perpendicular to the plane of the base. Using a cord, we marked the lines, continuing them at the corners to the intersection node.
The width of the blind area must be at least 60 centimeters. In this case, the size is checked by the eaves overhangs. Water from the roof should not fall onto the ground, but flow down the path. You should retreat 20 - 25 centimeters outward from the drainage border. The resulting value is measured from the foundation. We defined largest size and marked it along the entire perimeter. Different width blind areas are possible. But she looks worse. After all, the design of our home is also important to us.
Water should not get into the junction of the path and the foundation. Therefore, a slope is made from the base. The edge should be higher than the ground.

Design diagram of the blind area

The depth of the ditch under the blind area is calculated according to the height of the layers that will be poured into it:

  • 10 cm – clay for compacting and leveling the base;
  • 15 cm compacted sand;
  • 20 cm crushed stone;
  • 10 cm sand under the tiles.

Now my assistant received step-by-step instructions and began to dig a trench with his own hands along the foundation around the house to a depth of 55 centimeters. To prevent the edges from crumbling, he immediately installed formwork - knocked down boards. The edge of the shield should protrude several centimeters above the ground surface if the blind area is being filled.

Construction of a blind area made of ceramic tiles

Preparatory work, perimeter insulation: step-by-step instructions

On soils with normal moisture content, you can omit the clay and make the gravel layer smaller. In our case, the house is located in a lowland, there is a river nearby and enhanced waterproofing is needed. The connection of the blind area to the base of the house must be tight. To do this, the surface of the foundation is completely cleaned.
They poured clay onto the bottom with their own hands and, using a square, immediately compacted it with an inclination away from the building. The difference in height was 2 - 3 centimeters per width. Waterproofing was laid on top, following the step-by-step instructions. You can use regular film. Vadik decided to play it safe and make it last forever. The strip of roofing felt was cut 20 centimeters larger and bent along the line adjacent to the foundation.

Insulation and waterproofing of the blind area

Now at our building reliable protection from destruction by water. All moisture that comes from the soil will flow down the slope of the waterproofing.
The sand was poured in an even layer and compacted, maintaining the angle of inclination. The pressure strip attached to the base of the house an assembly of roofing felt on clay and geotextile laid on top of sand. The porous fabric will allow moisture to pass through and hold the gravel, preventing it from pushing through the sand. In the same way, the second layer of material was laid on the crushed stone. If the blind area is filled with concrete, then the thickness of the crushed stone layer is greater, up to the very top of the trench. To ensure good shrinkage, we poured water over everything and waited a few days.

Insulation of the blind area with foam

Filling the blind area with your own hands, step-by-step instructions

In areas with deep freezing of the soil, you can put insulation on the crushed stone yourself. It will be mineral wool or polystyrene foam, it is up to the owner to decide. Hygroscopic material needs protection from moisture. It is covered with a film and a metal mesh is laid on top. Along the abutment line, the waterproofing is attached to the surface of the foundation. The angle of inclination must be maintained on all pillow materials. This protects the base from destruction.

Filling the blind area with cement mortar

The blind area is poured along the beacons. The cords are stretched along the foundation and along the edge of the path at surface level. Every meter, a bitumen-impregnated board is installed and its upper end is positioned at the level of the marks. The solution is poured over it and the slope is determined. These strips remain in the concrete and serve as compensators for the linear expansion of the screed due to temperature changes. In places where there is a node of water supply and sewerage pipes, it is necessary to make bends under the path in advance.
It is difficult to do a large amount of work on concreting a blind area yourself. I use slats to separate them and fill a meter between them. Then I level it after all the work is completed and rub it in with dry cement - iron. I cover the junction of the base with the blind area with ebbs in the color of the finish. This prevents collapse and improves foundation design.

Step-by-step instructions for laying tiles with your own hands

Blind area from paving slabs

My friend is not limited in funds and makes it with his own hands construction works to protect the building to improve your level. Therefore it is important for him appearance yard He developed the design for the façade, turning the building into a castle. The protruding part of the foundation and the base are lined with natural stone. For the blind area I bought slabs of the same material.
We poured sand onto the second layer of geotextile and compacted it. Then I started laying out the tiles. Vadik poured water and filled the gaps. Working with paving slabs requires skill. My auxiliary worker was afraid of ruining everything and simply helped me. Once everything was in place, we secured the flashings, protecting the junction.

Due to geological features, the house is exposed to external factors not only from the atmosphere, but also from the soil. Installing a blind area around the house is one of the stages comprehensive protection, allowing to protect the building from manifestations of nature (rain, melt, groundwater). Roof and drainage system protects the walls and the house itself from water, but precipitation flows to the ground near the building and destroys the foundation. What is a blind area? Why do you need a foundation blind area, what is its purpose and how to do it yourself?

What is a blind area at home

A blind area is a covering around the perimeter of a house, designed to protect the foundation, basement and basement from water. It is made of waterproof material at a slope from the foundation.

Why do you need a blind area around the house (functions):

  • hydrobarrier - protecting the foundation of a building from moisture. First of all, rain and melt water are diverted away from the foundation using a blind area. In addition, the presence of a blind area imparts thermal insulation properties to the foundation;
  • comfort - the blind area can be used as a path around the house. A wide blind area can become the basis for arranging a recreation area or terrace near the house. With the correct calculation of the load, it is possible to organize the movement of a car or its parking along the blind area;
  • aesthetics - design of the site and local area, giving the structure completeness.
  • the blind area stabilizes the air-gas regime in the soil surrounding the foundation. The soil invariably contains oxygen, which is necessary for plant growth and the vital activity of soil microorganisms. Large pests also create passages for air to enter the soil;
  • eliminates the possibility of damage to the foundation due to frost heaving of soil. It occurs due to the fact that water, solidifying in the soil during the cold season, increases its volume. Soil heaving in itself does not pose any threat, but it creates a significant lateral load on the foundation of the house, which can result in a distortion of the foundation of the house, which will ultimately lead to the destruction of the building standing on it. Thus, the blind area allows you to distribute the load more evenly.

Types of blind areas around the house

Taking into account the fact that the period of operation of the blind area should be equal to the period of operation of the structure itself, special attention should be paid to the choice of material for its construction.

In practice, several approaches to making a blind area are used, but in general it is classified as either hard or soft.

Rigid blind area

1. Concrete blind area

The blind area is made of concrete in the vast majority of cases. Concrete is a reliable material, time-tested and proven by more than one generation of users. Almost every man has an idea of ​​how to make a concrete blind area. And knowing the nuances of pouring it, he can do the work with his own hands.

It is mostly used to protect the foundations of multi-story buildings. This is caused by two factors. Firstly, the difficulty of compacting the material (considerable effort is required). Secondly, to keep the asphalt in a condition suitable for pouring, its temperature should be about 120 degrees. Agree, it is difficult to make a blind area from asphalt without special equipment. Thirdly, when heated, asphalt releases harmful impurities, and therefore few users are ready to replace the clean air of a country house with a typical urban aroma.

3. Blind area made of ceramic tiles

It belongs to the category of hard because the tiles are laid on a concrete mortar. Clinker tiles are used as facing material, as they are more resistant to external influence. This blind area copes well with its functions, but the cost of clinker tiles is high. Therefore, its analogue, concrete paving slabs, has become more widespread.

Soft blind area

4. Blind area made of paving slabs (paving stones)

A relatively new direction in protecting the foundation from water. Despite the novelty of the material (or rather, the old one, since it is a prototype of paving stones - a cheaper analogue), laying paving slabs with your own hands does not cause any particular difficulties.

5. Blind area made of gravel (crushed stone) or natural stone

The gravel blind area (made of cobblestones, rubble stones) has not become popular for several reasons: the difficulty of compaction, the inconvenience of movement, the need to constantly correct the coating (it can be washed away by unorganized drainage), and the possibility of weeds sprouting. A blind area made of stone is a good option, but installation is more complex and expensive compared to tiles.

6. Hidden blind area around the house

In this case, the front material is the soil on which you can plant lawn grass, flowers, arrange flower beds. A blind area of ​​a hidden type is made according to general principle: removable upper layer ground, covered with a layer of waterproofing, a layer of sand and crushed stone. The difference is that the top of the pie is covered with geotextile or PVP membrane, on top of which soil is poured. It is not advisable to walk on a hidden blind area; there is a risk of damaging the profiled membrane and trampling the grass. But, if done correctly, it will serve faithfully for a long time.

Which blind area is better - made of paving slabs or concrete?

Each of the above types of blind area has its own advantages, disadvantages and construction features. According to statistics and reviews, today the most popular (most often used) blind areas are poured from concrete and laid out from tiles. Therefore, it would be correct within the article to consider what is better, concrete or paving slabs for the blind area?

This question is asked by many craftsmen and users. Practical operating experience indicates the effectiveness of the tiles. The advantages are as follows:

  • the ability to create a continuous, strong and stable blind area. At the same time, ensure the integrity concrete blind area much more difficult than tiled;
  • maintainability. The tiles can be dismantled completely or partially. Thus, the process of repairing a blind area or laying communications is significantly simplified. In the case of concrete, it is necessary to destroy part of the blind area, dispose of the concrete fractions, and restore it again after laying. Eliminating tile subsidence or replacing a defective element in a tile blind area is not difficult and will not take much time. And most importantly, the tiles can be reused;
  • reliability. The tiled blind area drains water well thanks to a large number seams. This allows us to assert that it does not deform as a result of soil heaving or water freezing. Water that has frozen on the surface of a concrete blind area can lead to local cracking of the material. At first, these cracks will not pose a threat, but each subsequent flooding will cause the crack to expand and the blind area to collapse.

    Another nuance is the location where the blind area adjoins the house. As you know, the blind area should not form a single structure from the foundations (should not be connected to it). Soil movement and freeze/thaw cycles will inevitably cause this bond to break. When laying tiles it is easier to ensure the required technological gap. In addition, the destruction of concrete most often occurs precisely at the place where it adjoins the foundation or plinth (the blind area comes off);

  • foundation insulation. The technology for laying paving slabs involves the arrangement of several layers, incl. the use of clay and the possibility of laying insulation. An insulated foundation blind area is an additional protection for the basement, ground floor, which reduces heat loss and ultimately leads to savings on home heating;
  • reduction in plinth height. With a rigid blind area (made of concrete), the minimum height of the plinth should be at least 500 mm. When soft (tiles, paving stones, gravel, a natural stone) a height of 300 mm will be sufficient. This reduces the cost of installing a plinth;
  • ease of work, no need for a reinforcing frame, minimum waste, minor dustiness of the work;
  • additional waterproofing of the foundation blind area. While the concrete blind area protects the foundation only from the influence surface waters(rain or melt), a clay hydraulic lock, which is made by forming a cushion for laying paving slabs, allows you to protect the base of the building from groundwater;
  • more aesthetically pleasing appearance compared to a concrete blind area. A variety of installation options, designs, sizes and colors allows you to create a unique blind area.

The main advantage that led to the use of concrete as a material for the blind area is its low cost. Buying paving slabs and materials for laying them will cost more, even if you do the installation yourself.

Cost of blind area of ​​a private house

In order not to be unfounded, we will give a brief comparative description, i.e. We will indicate in the table the prices for blind areas made of concrete and paving slabs. All prices for 2015, approximate, are presented for information purposes as a guideline for drawing up estimates.

The cost of a concrete blind area (width 1 m, thickness 10 cm)

Material Material consumption per 1 sq.m. Price The cost of a concrete blind area per 1 sq.m. rub.
Concrete M22, class B-15 1 RUB 3,500 350
For self-cooking concrete
per 1 cubic meter For 1 sq.m.
Cement M 500 320 kg 32 kg 200 rub/50 kg 128
Screenings or crushed stone (fraction 5-10 mm) 0.8 cubic meters 0.08 cubic meters 160
Sand 0.5 cubic meters 0.05 cubic meters 400-600 rub/m3 (the price is also affected by the loading location: quarry or delivery) 30
Water 190 l 19 l At local rate
Concrete additives*
For pillow
Geotextile, PVC film) 1 sq.m. 110-2500 rub/roll (50 sq.m.) 100
Sand 0.05-0.1 cubic meters Depending on the thickness of the layer and the composition of the finishing base for the tile 400-600 rub./m3. 25-50
0.1 cubic meters 1800-2000 cubic meters (the price is also affected by the loading location: quarry or delivery) 190
Reinforcement
Fittings, diameter 6 mm. 12 m.p. 10 r/m.p. 120
Reinforcing mesh 50x50, diameter 3 mm. 1 sq.m. 60 rub./piece (1000x2000) 60
Reinforcing mesh 150x150, diameter 3 mm. 1 sq.m. 33 RUR/piece (500x2000) 66
Formwork installation
Boards for formwork**
Beam 30x30 for spacers**
Total: ~ 800 rub/sq.m.

* We are talking about additives (plasticizers) that give concrete additional properties (strength, frost resistance). Adding plasticizers to the composition concrete mortar is at the discretion of the master. In the “classic” recipe given, their cost is not taken into account.

** to form the formwork when pouring a blind area, in practice, old boards or used plywood are used. Therefore, their cost is also taken into account.

The cost of a blind area made of paving slabs 1 meter wide

Material Material consumption per 1 sq.m. Price The cost of a blind area made of paving slabs per 1 sq.m. rub.
For pillow
Clay Depends on the soil and the desired thickness of the hydraulic lock 0.05-0.1 cubic meters. 250-400 rub/m3 (depending on the location of the quarry and the fat content of the clay) 15-30
Geotextile, PVC film 1 sq.m. 110-2500 rub/roll (50 sq.m.) 100
Sand 0.15-0.2 cubic meters Depending on the thickness of the layer and the composition of the finishing base for the tile 400-600 rub/m3 75-100
Screenings or crushed stone (fraction 3-10 mm) 0.1 cubic meters 1800-2000 cubic meters (the price is also affected by the loading location: quarry or delivery) 190
For the finishing layer
Cement M 500 10 kg. Depends on the purpose of the formwork 500 rub/50 kg 100
Sifted sand 2.5 - 10 kg. Depends on the purpose of the formwork 100 rub/50 kg 10
For the front layer
Tile Depends on the size of the tile. 50 pcs. for the “brick” shape 300-1,500 RUR/pcs. on average 400 rubles. for the “brick” shape 2000
Border 2 pcs. 75-300 rub/piece. depending on thickness 360
Water for irrigation sands and blind areas Before puddles form At local rate
Total: ~ 3000 rub/sq.m

How long does it take to install a blind area?

An important point, based on the experience of constructing blind areas of various types, we can give the approximate time for the construction of each of them. The calculation was made based on the total time spent by one person on making a blind area of ​​50 square meters.

  • Completion of all work on preparing the base, forming the formwork and pouring the concrete blind area takes approximately 40-50 minutes. per 1 sq.m. (20-25 minutes when using ready-made concrete).
  • Filling the pillow and laying tiles 1 sq.m. takes 60-70 minutes. Moreover, a significant amount of time is spent on the process of compacting the base.

It should be noted that with an increase square meters(area) the speed of work increases.

How to make a blind area around the house with your own hands - video

Construction of a blind area for a house - SNiP and GOST

The second aspect that needs to be taken into account before you start building a blind area with your own hands is the provisions and recommendations of regulatory documents. These include:

GOST 9128-97. Mixtures of asphalt concrete road, airfield and asphalt concrete. Contains recommendations on determining the angle of inclination of the blind area.

GOST 7473-94. Concrete mixtures. They contain requirements for the quality of concrete used for arranging the blind area. Required when arranging a blind area that serves as a driveway for a car.

SNiP 2.04.02-84. Water supply. External networks and structures. SNiP regulates the construction of a blind area around a well, contains recommendations for choosing the angle of inclination, as well as for arranging a castle made of clay or rich loam.

SNiP 2.02.01-83 Foundations of buildings and structures. Regulates the main parameters of the blind area device (dimensions):

1. Width of the blind area around the house (foundation)

Determined from the position of soil type. As you know, soil with different compositions subsides differently. For example, clay soil is divided into two types:

  • Type 1 soil does not sag under its own weight or its subsidence is no more than 50 mm and can be caused by external factors.
  • Type 2 soil can sag under its own weight.

Thus, based on soil data, the composition and thickness of the base layers for laying paving slabs is selected. Based on the provisions of SNiP, craftsmen determine how wide the blind area around the house should be.

It has been verified by practice that for type 1 soil the minimum width of the blind area should be at least 700 mm, for type 2 - at least 1,000 mm.

If there is normal soil on the site optimal width the blind area can be 800-1,000 mm. In this case, the width can be considered sufficient if it is greater than the overhang roofing material above load-bearing walls by 200 mm (for normal soil) and 600 mm for clay soil Type 2.

The final decision on how wide the foundation blind area should be depends on the users and the purpose of the blind area. Which may consist of the following: only foundation protection, protection + occasional human movement, protection + heavy pedestrian traffic (for example, a terrace or gazebo) or protection + car traffic.

Such parameters as the length and height (thickness) of the blind area are not regulated by SNiP. Users advise taking them as:

2. Length of the blind area around the house

3. Thickness (height) of the blind area around the house

Minimum thickness blind areas: at least 70 mm, optimally 100-150 mm.

Note. The height of the blind area is not determined to zero. It should rise above the soil by at least 50 mm.

For the blind area that serves as a pedestrian zone, the requirements are becoming more stringent. They mainly concern the design of the pillow. For a motor vehicle zone, it is advisable to do as much as possible solid foundation and when choosing paving slabs, give preference not to vibro-cast, but to vibro-pressed ones.

SNiP III-10-75 Landscaping. The standard regulates the installation location of the blind area. It should fit tightly to the base at an angle. At the same time, the slope of the blind area should be within 1-10% in the direction opposite to the load-bearing wall.

4. Slope of the blind area of ​​the house

The angle of inclination of the blind area is measured in percentages and degrees. For 1 m of blind area width, the slope should be 10-100 mm, i.e. 1-10%. In practice, the slope does not exceed 15-20 mm per 1 linear meter. This slope is invisible visually, but does an excellent job of draining water from the foundation and base of the house.

Note. A large slope can lead to the fact that the flow of water will increase speed when moving along the blind area and, gaining strength, quickly destroy its outer edge.

Another document worth considering is the “Schemes for operational quality control of construction, repair and construction and installation work" Based on it, you can study the permissible deviations from the given standards.

5. Expansion joint in the blind area (deformation, temperature)

To compensate for the movement of the blind area and reduce the pressure on the foundation, an expansion joint is provided - a gap between the wall (basement) and the blind area. A thermal seam is formed by installing a sheet of insulation or several layers of roofing felt to a vertical surface. Sometimes at the junction they install wooden board, which is then removed, and the place where it is installed is sealed (covered) with sand. This is a labor-intensive method, because removing a board from hardened concrete is quite difficult.

Conclusion

The information provided from the theoretical part will become a useful basis for constructing a blind area around the house with your own hands. Knowing how to properly make a blind area, you can be sure that the created structure will last a long time and effectively.

There is nothing secondary in construction. To all structural elements buildings and structures must be approached responsibly.

One of the final types of work at a construction site is the installation of a blind area. It is carried out upon completion of the construction of the house, in parallel with the construction of an external staircase or entrance to the garage, but after the facade of the building or at least the basement has been finished.

Blind area- this is a strip 0.6-1.2 m wide, adjacent to the foundation or plinth of a building with a slope, “descent” from it. The slope of the blind area must be at least 1% (1 cm per 1 m) and no more than 10% (10 cm per 1 m).

Do you need a blind area?

The main task of the blind area is to drain surface “rain and melt” water from the walls and foundation of the house. The blind area prevents the penetration of surface water to the base of the foundation, and is also decorative element external landscaping, forming a sidewalk around the house.

In addition, the blind area prevents the lawn or plants from growing close to the walls of the house, preventing excessive moisture in its structures and damage to the foundation by the roots of trees and shrubs.

Design of the blind area

The traditional blind area consists of two main layers - decorative coating and the underlying layer.

Substrate

The underlying layer serves to create a compacted and level base for further laying of the blind area covering. The following is used as a base layer: sand, crushed stone, clay. The choice of material depends on the top covering of the blind area.

Decorative coating

The covering of the blind area must first of all be waterproof and difficult to be washed away by water.

In the old days, the blind area was made of clay: they dug a shallow trench around the perimeter of the house and filled it with clay, which was compacted with a slope away from the house and moistened, creating a waterproof layer over the surface of which rain and melt water flowed.

Today, when constructing a blind area, clay is replaced with concrete - it makes it possible to obtain a monolithic surface without cracks, which is especially important when there is no confidence in the presence of waterproofing of the foundation. If the foundation is properly insulated, then piece materials can be used to construct the blind area - paving slabs (paving stones), crushed stone, slabs.

Blind area device

Blind area level

The height of the base depends on the type of material from which the blind area is made. If it is gravel or crushed stone, it is enough to raise the plinth to a height of 30 cm. If it is a hard and flat surface (for example, concrete or paving slabs), the height of the plinth must be increased to 50 cm.

Blind area width

The width of the blind area is set depending on the type of soil and the extension of the eaves of the roof. On ordinary soils, the width is taken to be 20 cm wider than the cornice (but not less than 60 cm), so that water flowing from the roof does not erode the soil and stagnate under the house. On subsiding soils, 20-30 cm beyond the border of the slopes of trenches or pits excavated under the foundation, but not less than 90 cm.

Slope of the blind area

For cobblestone and crushed stone blind areas, the transverse slope from the axis of the house is taken within 5-10% (5-10 cm per 1 m of width). For concrete and asphalt 3-5%. Moreover, the steeper the slope, the better the water is drained and the more inconvenient the blind area becomes as a walking path around the house.

The gap between the wall and the blind area

When constructing a blind area, you should remember the gap between it and the wall. Its purpose is to protect against damage and destruction of the waterproofing of basement walls. If there is no gap, then the blind area made of paving stones or slabs will put pressure on the wall under the influence of frost, and as a result of walking on it, it will settle and damage the insulation on the outer surface of the foundation wall. May also be harmed facing material, for example, tiles on the plinth crumble.

To prevent this, it is necessary to leave an expansion joint 1-2 cm thick and fill it with sand, extruded polystyrene foam or sealant.

Drainage around the blind area

Only a blind area of ​​3 or more meters wide can guarantee complete drainage of water from the foundation and its “dry mode”, which, of course, is not always realistic, so it is worth using additional protection - a storm drain and drainage system.

For rigid blind areas such as concrete and slabs, surface linear drainage is suitable - a drainage groove or gutter along the outer line of the blind area made of stone, concrete, plastic or asbestos-cement pipes, sawn in half lengthwise. And don't forget about their deviations!

Ready-made drainage elements equipped with upper protective grilles (plastic or polymer concrete) are good. Ready-made drainage trays with a drainage pipe and an upper grid, adapted for installation in the prepared plane of the foundation blind area.

Blind area made of paving slabs
(paving stones)

One of the most commonly used materials for blind areas is concrete paving stones. It is resistant to frost and temperature changes. Paving stones are available for sale different colors and shapes: rectangle, square, hexagon, wave, etc. The edges of the paving stones can be smooth or chamfered, which significantly reduces the risk of chipping the edges. Paving stones are produced with a thickness of 4-10 cm, a width of 6-20 cm and a length of 10-28 cm. For the construction of a blind area, elements with a thickness of 4-6 cm are most often used.

Stone paving stones is natural material and compared to concrete it does not have such a variety of shapes. Usually this is a cube or parallelepiped made of gray, red or yellow granite, as well as black basalt. Of course, it costs much more than its concrete counterparts.

Laying the blind area

Before starting work on constructing a blind area around the building, all work that could lead to damage to the blind area must be completed, namely:

  • the roof, eaves overhangs and canopies over the entrances were installed;
  • metal-coated window openings;
  • all fastenings are installed drainpipes and fire escapes.

Pegs are driven into the corners of the building, on which the height of the junction of the blind area and the plinth is marked, and according to these marks, the cord is secured along the entire perimeter of the building. A second line of pegs is installed along the outer edge of the blind area. They mark the height of the outer edge of the future concrete covering blind areas.

To drain rainwater, the blind area is made with a slope (at the base the coating thickness is 15 cm, and at the opposite edge 10 cm). The transverse slope from the base of the building is - 5% (5 cm per 1.0 m width).

First of all, it is necessary to determine the width of the blind area, which depends not only on the wishes of the customers. This parameter is largely determined by the type of soil and the width of the eaves of the roof. On ordinary soils, the blind area should be 20 cm wider than the eaves overhang (its minimum width is 60 cm). If the building is built on subsiding soils, the width of the blind area should be at least 90 cm. Sometimes it is made 1.0 m wide or more - in this case, the blind area, as a rule, serves as a path around the house.

The construction of the blind area begins with removing vegetation around the house and removing the plant layer to a depth of 15 cm. Carefully remove any remaining roots so that later sprouts that emerge do not destroy the coating.

Along the stretched twine, marking the longitudinal line of the edges of the blind area, a trench is manually torn off rectangular section(trough) for constructing a foundation for a blind area. The bottom of the trough is compacted.

Crushed stone grade M400 is manually scattered onto the prepared bottom of the trough in a layer of 15 cm at the base and 10 cm at the opposite edge, leveled to give the layer a design slope of 5%. The thickness of the crushed stone layer in a loose body must exceed the design by the loosening coefficient. A crushed stone surface is considered prepared when the mobility of individual particles is not felt.

On the prepared crushed stone base, a leveling (installation) layer of dry sand-cement mixture 3 cm thick is manually installed. Installation of the prefabricated blind area covering is carried out along the leveling layer. A tight fit of the slabs to the base is achieved by settling them when laying and immersing the slab in an installation layer of dry sand-cement mixture for the final landing of the slabs to a given level.

The laying of paving slabs should be carried out from any conventional line: the edge of the plinth, parallel to which the seams are located, or a milestone row laid perpendicular to the plinth, in both directions or to one side from it. The edges of the slabs are aligned using a stretched wire or cord located along the row being laid. The slabs are laid in transverse rows from edge to edge towards the slope.

To maintain the slope and evenness of the coating when laying paving slabs into the blind area, you must:

  • arrange a milestone row along or perpendicular to the base;
  • start laying the slabs from the edge of the blind area and lead towards the slope towards the base;
  • align the laid lightweight slabs by tapping with a rubber (wooden) hammer on a wooden spacer lying on the tile.

The leveling of the laid slabs is carried out by lightly tapping with wooden tampers. Recesses in the seams of adjacent slabs should not exceed 2 mm. The bead of sand-cement mixture formed at the edges of the slabs is cut off using a hand template.

The width of the seam between the plates should be 3-5 mm. The seams between the slabs are filled cement-sand mixture in a ratio of 1:3.

Concrete blind area

Concrete blind area is one of the cheapest and simple solutions. It is this material that allows the blind area to be waterproof.

The blind area should be at least 5 cm thick (recommended 7-10 cm). The concrete used for the blind area must correspond in frost resistance to road concrete and the grade must be at least M200.

Blind area from monolithic concrete should be installed on a sandy base, compacted to a density coefficient of at least 0.98. The minimum preparation thickness in this case is 10 cm.

Expansion joints

The concrete blind area must not only be separated from the wall by an expansion joint, but also separated by expansion joints every 6 m of its length. Practice shows that solid fill cracks in the first winter. For seams, a board tarred or treated with an antiseptic, 15-20 mm thick, laid on edge, is suitable.

Top surface wooden slats located at the level of the concrete surface, taking into account the slight slope of the blind area from the house. After this, concrete is laid, and the slats serve as so-called beacons along which the concrete surface is leveled.

Reinforcement of the blind area

To increase the service life of a concrete blind area, especially on heaving soils, it is recommended to reinforce it. This is necessary so that the blind area works in both compression and tension. Concrete works in compression, and reinforcement works in tension.

Reinforcement is in progress metal mesh with cells 100x100 mm or iron rods laid overlapping.

Ironing of the blind area

At the final stage of making a concrete blind area (about 1-2 hours after pouring the next section), in order to further strengthen the surface, it should be reinforced. Freshly poured concrete is sprinkled with cement, creating a layer 3-7 mm thick, and rubbed with a trowel. As a result, the material is protected from precipitation by a very durable and stable top layer, which has a characteristic dark blue, steel tint.

To prevent concrete from crumbling as it dries quickly, its surface should be covered (for 2-3 days) with damp burlap or plastic film.

After the concrete has hardened, it is necessary to seal the seam between the blind area and the wall of the house, for which bitumen or sealant is suitable.

The blind area works in the most unfavorable conditions for concrete, so it is good and correct to use only quality cement or concrete, to which it is desirable to add for protection against freezing.

Asphalt blind area

The base for the asphalt concrete blind area must be compacted with crushed stone (15 cm) or gravel with a particle size of 40-60 mm and pressed into the ground with a roller or tamper. An asphalt covering (3 cm) is laid on top.

The construction of a blind area made of asphalt concrete is quite complicated and this material cannot be called popular in private construction. In summer, when the heat is too high, the asphalt can soften and emit an unpleasant odor.

Blind area made of crushed stone

Blind area made of crushed stone - the most cheap option coverings. This perfect solution at high level groundwater and in the case where drainage is carried out around the building, since crushed stone facilitates the penetration of surface water. Instead of crushed stone, you can use gravel, pebbles, and expanded clay. It is recommended to use a crushed stone fraction of 8-32 mm.

A special geotextile material is laid on compacted continental soil, and crushed stone is scattered on top of it - without backfilling with sand. Geotextiles prevent coarse granules from mixing with the soil and preventing weeds from germinating. The thickness of the crushed stone layer is about 10 cm.

However, if there is unorganized drainage from the roof (that is, when water flows not through the gutters, but directly from the entire slope), the coating will have to be regularly corrected.

It should be taken into account that granules of the same size cannot be compacted tightly, therefore, walking on them will be uncomfortable.

  • Date: 08/29/2014
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Modern construction technologies have improved so much that often the blind area made around the building is practically indistinguishable from the base and looks like a natural continuation of it. Often it looks like a path or a beautiful sidewalk laid around the perimeter of the building. However, despite the sometimes excessive decorative look, its main task still remains to protect the foundation of the building from storm and flood waters.

The tightness of the junction of the blind area to the base: why is this important

To effectively ensure water drainage, the blind area is always performed with a slight slope in the direction from the foundation of the building. This slope can vary from 3º to 7º. And it is vitally important for the entire building to ensure a tight connection of the blind area to the foundation along the entire perimeter of the building. If the tightness between the base and the surface of the blind area is broken, then in this case rainwater will inevitably fall into the gap between the base and the blind area, saturating the soil and the foundation material itself with water.

If, due to a leak in the adjoining blind area, the building enters the winter with excess moisture inside the foundation and in the soil around it, then in winter, due to freezing, deformation of the foundation will inevitably occur.

And this is fraught with cracks in the walls of the building, or even destruction of the foundation itself.

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Standard scheme for making a blind area

When using almost the same materials as when. This is sand, gravel (to reduce the cost of materials, it is often replaced with large crushed stone or broken bricks), as well as working surface material: asphalt, concrete, cobblestones or paving slabs.

The structure of the blind area itself (or, as it is often called, “pie”) has remained unchanged for decades, if not centuries. First, a cushion is made of sand, then of gravel (or of materials replacing it) and a finishing layer with expansion joints.

In order to properly arrange and ensure reliable connection of the blind area to the foundation, you need to take a very responsible approach to all stages of its arrangement. At the first stage, you need to remove the top fertile layer of soil. And although construction textbooks give figures - 15 cm on normal soil and 30 cm on heaving soil, ideally it is better to remove the soil until you get to the sandy or clay layer.

However, if the thickness of the fertile soil layer on the site is 1-1.5, or even 2 m, then performing such a task becomes problematic. Usually a depth of 50-60 cm is sufficient, but given that such a trench has to be dug along the entire perimeter of the building, the work will not be easy. However, it must be done in such a way that there are no plant roots left in the soil, since even a small root, when germinating, can break through asphalt or concrete, destroying all your efforts to create a complete blind area.

The blind area must have a slope so that water flows into the ground.

Next, a ball of sand is poured into the dug trench and compacted tightly. Sometimes, to better compact the sand, it is poured with plenty of water. Even better is to replace sand with clay, if possible, since clay is waterproof. However, clay is suitable for a pillow only if the content of sand particles in it does not exceed 10%, otherwise heaving will occur. Clay needs to be compacted even more thoroughly than sand. It is best to use a vibrating plate to compact it.

Having arranged a sand or clay cushion, they proceed to filling the trench with gravel or crushed stone. Can also be used broken brick, although it is not as reliable as the listed materials. The main task of this pillow is the absorption and removal of capillary water, the accumulation of which in any case cannot be avoided.

If this is not done, then, accumulating under the waterproof canvas of the blind area, this moisture will freeze in winter and tear it. This will be especially felt in the area where the blind area adjoins the house. Important detail: if the site has high groundwater, then you need to take care in advance to protect the gravel bed from silting. To do this, it is best to separate the sand and gravel cushion with geotextiles.

After completing the arrangement of the gravel or crushed stone layer, the perimeter of the future blind area is outlined by the established curb stone. In the space limited on one side by the base of the building, and on the other by the curb, the blind area itself is arranged. It can be made of asphalt, concrete, brick, cobblestones or paving slabs. In the first two cases, its working surface must be reinforced.

At the final stage of constructing the blind area, it is imperative to install expansion joints. Such seams are needed to minimize deformation of the working surface. They are done every 1.5-2 m along the entire length of the blind area. For their installation, you can use damper tape, foamed polyethylene, but most often in private construction they use boards impregnated with resin and laid on edge with a thickness of 15-20 mm.

To arrange and seal the blind area you will need the following tools:

  • bayonet shovel;
  • shovel;
  • vibrating plate;
  • concrete mixer;
  • rubberized mallet (if arranged);
  • Master OK;
  • bullet urethane sealant.

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Why does the base not fit tightly to the blind area?

Unfortunately, during construction, little attention is paid to the issue of sealing the contact of the blind area with the building's base. And they only realize it when a gap of several centimeters appears between the base and the blind area, and water pours into it with might and main during rain.

Why does this happen? When constructing a blind area, there is an unwritten rule: the wider it is, the better for the foundation, especially for its underground part. In any case, the width of the blind area should be at least 20 cm greater than the projections of the roof slopes. Therefore, in most cases, its width ranges from 60-90 cm, and in the case where the building is built on easily compressible soil, the width can exceed 1 m.

Let's remember school course physics. Any physical body When heated it expands and when cooled it contracts. And the laid blind area is no exception. Therefore, the slightest violation of the blind area laying technology can lead to very sad consequences.

For example, an insufficiently compacted base can lead to subsidence of the soil under the blind area, and incorrectly executed expansion joints or their absence threaten the destruction of the blind area. But most often, the processes of alternating heating and cooling of the blind area lead to the fact that the laid blind area simply moves away from the foundation, forming a gap, sometimes several centimeters wide.

This happens because the base is not adjacent to the blind area, but is made as a single system. with temperature changes, although it is an insignificant value, nevertheless it is quite enough for a crack to appear at the junction of the blind area and the plinth, which will only increase over time (and, accordingly, with new heaving of the soil).

That is why, when making a blind area, it is necessary to install not only longitudinal expansion joints, but also an expansion joint along the perimeter of the foundation at the point where the blind area adjoins the foundation. Such expansion joint It is done using a damper tape, or single-component bullet-urethane sealants are used for its arrangement. For these purposes, you can use emphymastics, hermaflex 147 or Sikaflekx Construction.

However, there are also our comrades who are only still thinking, and its components. It was precisely for them that I wrote this material.

Why do you need a foundation blind area?

Let's think together about why a foundation blind area is needed, what functions it performs, and what would happen if it was not done.

The first thing a foundation blind area is needed for is to protect the entire underground part of the house from precipitation. Rain or snow, flowing down the walls of the house or simply flowing off the roof, if a drainage system is not made, ends up on the ground next to the house.

Moisture is absorbed into the soil and gradually reaches concrete base building. And then everything is as in the saying “a drop wears away a stone.” Moisture affects the concrete base, freezing during frosts and thawing during thaws.

Moisture penetrates through the smallest capillaries and every day, millimeter by millimeter, it widens the cracks in the foundation and destroys it. To prevent this from happening, builders build a blind area around the house.

How to make foundation blind area effective

To understand how to make a foundation blind area, let’s take the very first purpose of this node and see how it can be implemented. can be implemented like this:

  1. Waterproofness of the blind area.
  2. Moisture removal by drainage.

This means that we need to make a water-impermeable strip around the house and remove moisture from it using drainage ditch. What this simple unit looks like can be seen in the diagram.

The blind area can be made from any waterproof material, or any waterproof material can be included in its composition.

You can make a blind area from concrete, or you can make a blind area from paving slabs, and under it put a layer of PVC banner fabric, which does not rot in the ground and does not allow moisture to pass through at all.

Foundation plinth and blind area - expansion joint

In the place where the base and the foundation blind area touch, our house has one weak node - the place where they connect. If done in this place rigid mount, fill it with concrete or fix it, then sooner or later there will still be a crack, there will still be destruction of this unit.

This happens because heavy house with the foundation and the unloaded soil around it move differently depending on the seasons or on. To ensure that there are no cracks in this unit, builders make an expansion joint from any plastic material that can undergo limited deformation. Previously, this knot was covered with plastic clay. Nowadays the expansion joint is made of penoplex.

Penoplex does not allow water to pass through and is a highly effective insulation material. Thus, this material prevents water from penetrating between the base and the foundation blind area and prevents the base of the house from freezing along this node.

How to make a concrete foundation blind area

We have already discussed how to make an insulated soft blind area. Now let's discuss how to make a concrete foundation blind area.

In regions where long time V winter period, a solid rigid belt around the house is not the most the best option. However, he also has the right to life if performed correctly and high-quality insulation both the blind area and the base.

  1. So, to begin with, we remove the soil around the base of the house to the depth necessary for arranging a cushion for the blind area.
  2. Then we backfill, but with clean sand - we form a pillow. A sand thickness of 15 cm will be sufficient. Next, we place PVC banner fabric, which will drain moisture into the drainage ditch.
  3. After this, we make another 10 cm layer of sand to protect the PVC fabric from damage. Then we lay the reinforcing mesh and make formwork for pouring concrete.
  4. Next, pour concrete - a 15 cm screed will be enough to make the blind area strong and withstand not only the movement of an adult, but also small garden equipment type of motor plough, etc.

How can you save on the blind area?

The question arises: is it possible to save money on this unit and make the blind area cheaply? It turns out that it is possible.

  1. Firstly, you can not buy new PVC banner fabric for water drainage at 400 rubles per 1 sq.m., but buy old banners from advertising agencies. It's up to you to agree on the price. I managed to buy 1 banner 6 by 3 meters for 100 rubles, which is 18 square meters - without holes or scuffs. As you can see, you can save several thousand rubles on banner fabric alone.
  2. Secondly, you can use for the cushion not pure sand, but used ASG, which is removed during the repair of city roads. A clean sand machine costs 7,000 rubles, and a used PGS machine costs 1,500 rubles. The savings are obvious.
  3. And finally, it is not necessary to hire a professional team of builders in order to make a foundation blind area. This is not a roof or the foundation itself - it is quite possible to make a blind area with your own hands. To do this, you only need accuracy and patience, as well as a correct understanding of the diagram that is published in this material.

So we’ve figured out why you need a foundation blind area and how you can do it economically.