Greetings, friends. Alexander Alexandrov is the author of this blog!
Today I will tell you how to make a blind area with your own hands.
When building a private house should take into account various nuances. Including – prevention of warming the basement with rainwater. Constant water flow under the foundation can lead to very undesirable consequences. The effect of atmospheric moisture on the concrete foundation leads to cracks and other damage. In these cracks begin to grow plant roots and produce a destructive effect on the foundation.
Sometimes when building a building, the builders for some reason forget the existence of such a problem, and the owner of the house has to solve it himself. Some owners are not aware of the need to protect the foundation of the building, and this significantly reduces the operational life of the dwelling.
To prevent water from flowing under the foundation, a blind area is made – a special reinforcement of the structure’s perimeter. If you have experience in construction, this element of the house can be made independently, thereby saving on the services of specialists.
So, how to make a blind area yourself?
The blind area is designed to perform the following important functions:
- protection of the foundation of the structure from such destructive factors as moisture, plant roots, and so on;
- removal of rain or melt water from the walls of the house into the drainage system, for which the blind area is provided with chutes for drainage – this design reduces the risk of dampness of the foundation;
- improving the aesthetic appearance of the house, giving it harmony and completeness;
- reduction of heat losses in the cold season.
In addition to fulfilling its main purpose, the blind area can additionally be used as a walkway around the perimeter of the house. Also pavement tiles are laid on the concrete blind area.
How is the blind area
The basis of the blind area is the underlying layer, on top of which the covering layer is applied. Often, to create them using different materials. To ensure drainage from the walls of the structure, the surface of the blind area should have a slight slope.
The covering layer is often made of concrete.
In this case, the surface of the base layer should be horizontal, while the slope of the surface of the covering layer is created when concrete is poured. The standard slope is five centimeters per meter.
The underlying layer is most often made of clay, crushed stone or gravel. The most practical material is wrinkled clay due to the fact that it does not pass water. Usually the underlying layer is made with a thickness of 0.25 to 0.3 meters. When using clay of sufficient thickness for the underlying layer will be from 0.15 to 0.2 meters.
If crushed stone or gravel is used when creating the underlying layer, then a layer of sand from 0.07 to 0.1 meter thick should be laid between it and the covering layer.
The covering layer is made of durable and waterproof material – natural stone, asphalt, concrete. In some cases, a brick or pavement tile is used for this.
The first step in the preparation is to establish the main parameters of the future design. The standard minimum blind area is 0.6 meters. However, its design must take into account the following factors, including those related to the features of the architecture and design of the building:
- The position of the edge of the eaves of the house roof: the edge of the blind area must be at least 0.25-0.3 meters beyond this edge. This will prevent water from flowing from the roof to the ground in the absence of a drain or problems with it.
- Compatibility of the blind area with the overall design of the structure and the surrounding landscape.
- Features of the soil around the building. So, if the house is surrounded by subsiding ground, then the minimum recommended width of the blind area is one meter. This size provides the convenience of using a blind area as a walkway.
- Climate features of the area in which the house is located.
- The materials to be used for the construction of the blind area. So, if you make a covering layer of paving slabs, then the slope can be made smaller than in the case of using crushed stone.
After establishing the value of the blind area width acceptable in this situation, it is necessary to determine its angle of inclination. To ensure effective drainage, the value of this angle should lie between two and five degrees.
The slope of the blind area can be created both during the laying of the underlying layer and during the installation of the outer covering. The choice of a particular approach is determined by the materials used.
The next step in preparing the construction of the blind area is the calculation of the required volume of materials and the selection of the necessary tools. To lay the bottom layer you need crushed stone, sand or clay.
The most common material for the coating layer is concrete. If you intend to use the blind area in the construction of it, then you will need the following tools and additional materials:
- a concrete mixer or trough for mixing cement mortar;
- reinforcing rods;
- bayonet shovels for digging the soil and shovels to work with the solution;
- ruler or tape measure;
Blind area do it yourself
The first step in the construction of the blind area is the marking of the area in front of the building. To do this, you need to drive the pegs along the perimeter of the building into the ground at the required distance from the wall and connect them with a string.
2. Prokopka trench under the blind area
After this operation, you need to dig between the stretched twine and the wall of the house a trench, the depth of which will be determined by the selected material. Typically, the thickness of the blind area of concrete is 0.25 meters. In this case, the thickness of the surface finish is not taken into account.
After the trench is ready for the blind area, it is necessary to prevent unwanted growth of plants in it, the roots of which may have a destructive effect on the structure in the future. To do this, the soil is treated in a trench and close to it with special herbicides. If trees grow close to the future blind area, their roots should be cut.
You can also lay a geotextile, but it is more expensive
Trenching is not always a necessary procedure. If the soil around the house is soft enough, then it will be enough to ram to the appropriate depth.
3. Installation of formwork
The next step is to build the formwork. To do this, you can use uncut boards at least 20 millimeters thick. Boards are installed along the outer border of the pit. As the supports you can use the bars of wood.
4. Creating a base layer
After installation of the formwork, it is necessary to tamp the bottom of the trench and fill it with clay so that the layer thickness is 50 millimeters. Clay should be tightly compacted, and then pour a sand layer 100 millimeters thick on it, which should also be compacted. To seal the sand layer was high quality, sand should be moistened. The final step of this stage of work is laying the rubble on top of the sand layer.
Soil tamping at the bottom of the pit is a necessary step in the construction of the blind area. If you do not do this, then the blind area in the future may sink under its own weight. In order to completely eliminate water seepage through the blind area, a layer of clay can be separated from the subsequent layers by a waterproofing material, for example, a film of polyvinyl chloride or polyethylene.
5. Installation of reinforcing mesh
After the preparation of the pillow is completed, the reinforcement is laid on the surface of the rubble layer so that the reinforcing mesh is obtained. In this case, the distance between the rods should be from 100 to 150 millimeters. The intersection of the rods must be tied with steel wire. The presence of the reinforcing mesh ensures the strength of the blind area and its ability to withstand various loads.
Instead of reinforcing bars, you can use ready-made reinforcing mesh.
An important nuance in the reinforcement is to ensure that the reinforcement is completely covered with cement mortar. To do this, you can lay the grid on the bars of wood, which are gradually removed in the process of concreting.
6. Creation of a temperature weld
Where the blind area is in contact with the wall of the building, a temperature joint should be created, the width of which should be approximately 15 millimeters. Sand filled with gravel or bitumen is used to fill the joint space.
To create a heat insulating layer between the pavement and the wall of the house, you can also use plates made of extruded polystyrene foam or foam. It is important to ensure a tight fit to each other plates of insulation.
7. Pouring concrete
The next stage of work is the pouring of the concrete solution. To do this, you first need to lay across the trench rails of wood so that the distance between them was 2.3-2.5 meters. The purpose of these slats is to create expansion joints, ensuring the normal performance characteristics of the structure. The width of the rails should be such that their edges coincide with the level of the surface of the concrete layer. To prevent the destruction of the rails by bacteria and fungus, the wood must be treated with an antiseptic solution and covered with a layer of bitumen.
Standard concrete solution is prepared from cement (one part), sand (two parts) and small gravel (three parts). It is advisable to use river or sea sand. If ordinary sand from a pit is used, it is first necessary to perform its washing to remove various impurities.
Sand washing is performed twice or three times. To do this, you can use a concrete mixer. When washing, sand is poured into a concrete mixer, filled with water and stirred for several minutes. After that, the mixer is turned off and the water is drained. If this procedure is neglected, then in the future the erosion of the blind area with water is possible.
Pouring concrete is done immediately with one layer. Otherwise, there may be cracks in the future between areas that have been flooded at different times. Therefore, even if it is impossible to fill in all the concrete in one day for some reason, then the next day the work should be fully completed.
To prevent the formation of cracks and defects in the future, it is important to ensure the high quality of the cement slurry. Therefore, it is best to cook it in a concrete mixer.
If during the construction of the formwork hot weather was established, then the best time to work is early morning or evening.
8. Leveling the concrete surface
After the concrete layer has been poured in and has not yet hardened, the surface must be leveled and a necessary slope must be created. A rule is applied to perform this procedure. If this tool is not available, you can use an ordinary wooden lath with a smooth and even surface. To ensure the evenness, smoothness and proper inclination of the surface, you should use special beacons as landmarks.
Upon completion of the work to create a covering layer, the surface of the concrete must be covered with a sack moistened with water. This fabric needs to be moistened regularly, preventing it from drying out. This will prevent the formation of cracks in the concrete during its gradual hardening.
9. Finishing and decorative works
The process of hardening of concrete lasts from two to three weeks. After this time period has passed, and the concrete has gained the necessary strength, you can remove the formwork and proceed to finishing and decorating its surface. To do this, you can use sheets of porcelain, tile for sidewalks. or something else.
Blind area at home with their own hands – video
Well, that’s all, friends.
Thus, creating a blind area is not a very difficult construction job. Following the instructions, you can do this work yourself, and only spend money on building materials.
Do not pass by:
Sources: http://svoidomstroim.ru/blagoustrojstvo/otmostka-vokrug-doma-svoimi-rukami-poshagovaya-instrukciya-s-video.html, http://domzastroika.ru/foundation/ukladka-otmostki-svoimi-rukami. html, http://rukozhopim.ru/stroitelstvo/otmostka-svoimi-rukami-poshagovaya-in/