The blind area around the house is a special structure that is designed to drain atmospheric precipitation and protecting the foundation from premature destruction. Also, a blind area is necessary in conditions of heaving soil or in areas with high level groundwater, which can undermine the foundation. Let's take a closer look at how the blind area is done with your own hands, as well as which options for its implementation are most effective.
In addition to protecting the foundation, the blind area also performs practical and design functions. Very often it is used as a path, so it must have sufficient hardness and abrasion resistance. When choosing a blind area, you should also take into account the landscape design and exterior of the house. The correct blind area around the house helps to highlight architectural style buildings, make local area more accurate and practical.
The pouring of the blind area can be carried out simultaneously with the construction of the foundation. However, it can be made after finishing finishing works. If you neglect this point, over time, cracks may appear in the foundation, and the thermal insulation performance of the structure will decrease. Thus, the role of the blind area at home should not be underestimated. This is one of the main stages of building a house, which directly affects the quality of the structure. 
Construction of a blind area around the house
Before you start building a blind area with your own hands, you need to decide on the materials from which it will be made. Most often, concrete, asphalt, bricks, wood, reinforced concrete slabs or tiles. The correct blind area around the house must have at least two layers. Upper layer contains the main covering, and the lower one is a cushion of sand, small crushed stone, gritsovka or clay.
Ideally, the installation of a blind area around the house should be carried out simultaneously with the foundation. The width of the blind area should be about 80 - 100 cm or 20 - 30 cm more than the cornice. The wider the blind area, the faster the water drains. In this case, you should remember the slope, which should be 3 – 7ᵒС. A small drainage groove can be made along the perimeter of the blind area. This will prevent water from stagnating during heavy rainfalls or when snow melts. 
How to make a blind area with your own hands
Making a blind area with your own hands is quite easy. The construction process does not require special knowledge and is carried out in several stages:
- Preparing the base.
Installing a blind area with your own hands begins with leveling the surface, removing plant roots, removing the top layer of soil with a shovel and treating the soil with herbicides. It is necessary to install boundary boards around the perimeter and make a sand cushion. To do this, a layer of sand is poured onto the prepared surface, compacted and filled with water. Next, a layer of crushed stone or broken brick is poured.
- Waterproofing and insulation.
Insulating the blind area allows you to increase the thermal insulation of the foundation, which is especially important if the house has a cellar or ground floor. Polystyrene, foam glass or penoplex can be used as insulation. The air gap between the concrete layer and the ground can reach 15 cm. The blind area is waterproofed using PVC film, bitumen or roofing felt. 
- Installation of temperature cuts.
Temperature cuts can be made using storm drains or flat slate. It is necessary to leave an expansion joint between the wall and the blind area by placing roofing material, sealant or bitumen in it.
- Pouring concrete.
Concrete for a blind area can be made by combining 0.5 shares of water, 1 share of cement, 3 shares of sand and 4 shares of crushed stone. It is better to take grade M-300 cement. Filling is carried out carefully within the boundary boards.
- Ironing.
15 - 20 minutes after pouring the solution, the surface is sprinkled with dry cement and smoothed with a spatula. Thanks to this technique, the blind area is stronger, smoother and more moisture-resistant.
The installation of a blind area around the house can be made from concrete slabs. As in the first option, the base is prepared for this, after which the finished slabs are laid out and bitumen is poured. Also, recently, profiled membranes have become increasingly popular, which are placed directly on the ground, covered with crushed stone and sand, after which any covering is installed.
Alternative options for home blind area
The most popular option in our country is a concrete blind area 15 cm thick. If previously this type of blind area was the most affordable, now a wide variety has appeared building materials, insulation and waterproofing films, with the help of which cost of blind area around the house can be significantly reduced. Let's look at a few alternative options installing a blind area with your own hands.
Soft blind area for difficult soils
Soft blind area is one of the most simple options blind area devices, which can be used for heaving soils. It is performed in several stages.
Blind area with rubemast
Rubemast is inexpensive waterproofing material, made on the basis of fiberglass or fiberglass with bitumen impregnation. Using rubemast, you can build a high-quality blind area, adhering to the following action plan:
Geotextile blind area to protect against weeds
Installation of a blind area made of geotextiles is carried out in several stages:
Construction of a blind area in Finnish
This type of blind area is widely used in construction Finnish houses. It is radically different from the technologies familiar in our area and is carried out according to the following principle:
- It is laid around the perimeter of the house corrugated pipe with holes.
- Gravel is poured over the pipe, overlapping foam is installed and covered with soil.
- Next, the pipe is connected to drain wells.
- Crushed stone and decorative pebbles are poured at a distance of about 40 cm from the walls of the building.
The Finnish blind area is quite effective, drains water well and prevents freezing of the foundation.
Russian blind area - cheap and cheerful
This version of the blind area is very unusual and was invented by Russian craftsmen. It is performed using glass bottles in several stages:
- It is poured onto a small sand cushion thin layer concrete.
- Next, ordinary glass bottles are laid, and the next layer of concrete is poured.
- After this, reinforcement is performed, and the next layer of concrete blind area is poured. If necessary, the surface is subjected to ironing, i.e. sprinkled with dry cement.
The advantage of this technique is the absence expansion joints and low concrete consumption. In addition, the bottles leave an air gap in the blind area, increasing its thermal insulation without additional insulation.
In general, there are quite a lot of options for making a blind area around the house. If desired, it can be made of different heights, decorated with natural or artificial stone, tiles, cover with pebbles or crushed stone. 
Video Blind area device
There is a popular story about formwork devices and blind area pouring.
Reading time ≈ 8 minutes
To protect the foundation from the destructive effects of precipitation, a concrete blind area is used around the house. Such work can be trusted professional builders or do them yourself if you have the appropriate skills.
Purpose of the blind area
The main purpose of the blind area is to protect the house, or rather, its foundation. Not everyone understands what needs to be protected from a home. In fact, any structure may not withstand some natural “surprises”.
Let's consider what dangers may await owners of private houses. First of all, it is important to understand what type of soil the house is built on. Basically, soil is divided into two main types:
- not heaving;
- heaving.
You shouldn’t expect a catch from the non-fuzzy option.
But heaving soil is subject to frost heaving. Taking into account such soil characteristics, a suitable type of foundation is determined. It happens:
- shallow;
- recessed
If you ignore all the recommendations, water flows arising from heavy rainfall and melting snow will be actively absorbed by the soil and then erode the foundation of the house. Of course, such Negative consequences do not pass without a trace. The foundation collapses, and behind it cracks appear on the walls. All this leads to the need for urgent repairs.
Things are completely different when the blind area is already done. An inclined plane directs water flows in the opposite direction from the foundation.
If an area with moisture-saturated soil is chosen for building a house, a drainage system or drainage system must be built to drain the water. storm sewer.
Attention is also paid to the roof structure, namely the overhangs. They should be approximately 25 cm away from the walls. However, even all this is not enough to protect the building from the negative effects of precipitation.
Rainwater, under the influence of the wind, still falls on the walls, flows off them and concentrates at the base of the house. And in these cases, it will no longer be possible to do without blind areas.
However, the blind area was not limited to the protective characteristics. This additional design It also serves as an excellent insulator, preventing the foundation, basement and ground floor from freezing.
Blind areas also help increase the architectural attractiveness of the house. Some designers when creating landscape project Be sure to pay attention to blind areas, considering them one of the most important elements with which you can significantly improve the landscape aesthetics of the site.
Tools and materials
To build a high-quality blind area, of course, you need to follow the proposed step by step instructions. It will guide you in what order certain actions need to be performed. However, the final result depends not only on how correctly the work is carried out.
In many ways, the effectiveness of the design will depend on what quality characteristics the materials will accompany, as well as whether it will be possible to prepare concrete mortar the required strength class.
In addition to this, keep construction works You can do it yourself, but only if you have the appropriate construction tools. For this reason, before starting work, you need to purchase all the necessary tools or borrow them from friends.
Concrete mortar can be ordered from construction organization, but in such cases you will have to pay not only the cost of the material.
You will need to spend additional money on the services provided. However, these funds do not need to be spent; you can make the concrete solution yourself.
So, for work you will need to take:
- coarse sifted sand (it is important to exclude the presence of clay in it);
- granite crushed stone (size 20×40 mm or 5×20 mm);
- Portland cement (grade M500 or M400);
- fittings (diameter from 8 to 10 mm);
- steel wire;
- extruded polystyrene foam;
- geotextiles (as an alternative, you can use construction polyethylene, the thickness of which should be 30-50 microns);
- boards.
To make mixing easier concrete mixture, it is good to have a concrete mixer with a total volume of up to 200 liters. However, this device alone will not work. It is also necessary to prepare:
- shovel;
- buckets;
- a sieve with which the sand will be sifted (as an alternative, in the absence of such a sieve, you can use armored mesh from the bed);
- Master OK;
- building level;
- laser level;
- rule;
- grater
It is also important to have any source of water and power nearby if used. electric model concrete mixers.
Once you can decide on the brands of materials, you can begin preparing the mixture. It is better to install the concrete mixer in the place closest to the crushed stone. Otherwise, you will have to carry it in buckets, making the task a little more difficult for yourself.
Water is also needed: you will either have to carry it in buckets, or take advantage of a more rational proposal by connecting a long hose to a water source.
You will need approximately the same amount of water as cement. Although sometimes this amount may vary depending on the moisture content of the crushed stone and sand. For this reason, it is impossible to get an exact recipe; you have to do something “by eye”.
When preparing the mixture, the order in which the materials are added is important. The most important thing is the need to fill the concrete mixer drum with approximately 8 liters of water. Next, the device turns on, the drum begins to rotate, at this moment all other ingredients are poured in according to the following scheme:
- They pour in the cement and wait until it is well mixed and a substance that looks like “gray milk” is obtained (if unmixed cement is observed on the walls of the unit, the concrete mixer is stopped, the cement is scraped off the walls using a trowel, and then the device is started again).
- Add sand and add a small amount of water.
- They fill up with crushed stone.
After the mixture has been stirred for several minutes, you need to visually evaluate the composition and decide whether more water needs to be added to the mixture.
To get a strong and reliable blind area around the house, you need to prepare a concrete mixture with your own hands strictly according to the recommendations.
Work on the formation of the blind area
It is more correct to build the blind area initially, and not after the house is completely erected. This requirement is not put forward by chance.
Firstly, such work is accompanied by the risk of exposing heavy pollution walls of the house, because in the process of performing tasks, splashes fly in different directions.
Secondly, basement thermal insulation should be installed only with an emphasis on the thermal insulation of the blind area. And if you have an already constructed blind area, it will be easier to erect walls, since there is already a surface on which scaffolding can be placed.
To create a blind area, you must perform five sequential steps.
First, they dig a trench into which the concrete mixture will be poured. The width of such a trench should be from 80 to 100 cm. By the way, it is not at all necessary to measure the width of the blind area with the existing overhangs. When digging a trench, it is rather important to decide whether it is necessary to create storm drains or not.
The depth of the trench may vary. First of all, it is important to remove the layer of soil with signs of vegetation (with particles of the plant root system). Sometimes you have to dig a trench up to one meter deep, and sometimes 10 cm is enough to remove vegetation cover. However, in any case, you need to continue to go deeper until a hard layer is reached, when it will be difficult for the shovel to enter the ground.
Then move on to the next step. Since the blind area is constructed with insulation, geofabric is laid at the bottom of the dug trench. If you really need to save at least a little, polyethylene can be used instead of geofabric. Such a substrate can act as an effective obstacle to plant growth if some seed remains in the ground.
Next, crushed stone is poured into the trench in an even layer, which must be compacted. Another layer of waterproofing is laid on top of the crushed stone. It is recommended to use fiberglass here. Next, a layer of sand up to 20 cm high is poured. It is important to exclude the presence of clay in it. Using the rule, the surface of the sand flooring is leveled and then compacted.
After this, the sand is watered and compacted again to obtain a dense base.
If necessary, small trenches are dug in the sand into which storm drains are installed. It is important to install rainwater inlets on a slope. If it is laid horizontally, precipitation will not be able to drain. After laying the storm water inlets, the surface is leveled and compacted again.
Now there is a need to build a formwork that will act as a beacon when pouring the concrete mixture. The boards are placed around the perimeter of the blind area. Next, foam plastic is laid on top of the sand, which acts as insulation, so it must fit tightly to the foundation.
If necessary, penoplex sheets are secured by drilling holes and hammering rods into them. When all the rods are installed, they are connected, as in the photo, using wire.
The last step left is to pour the concrete mixture. When pouring, it is important to take into account that the risk of cracking from temperature changes is typical for a huge slab. For this reason, it is better to use a little construction trick. Along the entire perimeter of the formwork, boards are placed at an angle. They won't let you create monolithic slab, and will also act as beacons indicating how to pour the mixture to ensure the slope of the blind area.
The minimum height of the blind area should be 10-15 cm. It must be above the ground surface. The height of the blind area at the foundation, accordingly, should be 1-2 cm higher than the specified indicator.
The solution is poured, strictly monitoring the preservation of the angle of inclination. The next day the surface is rubbed with a grater. Well, at the end of all the work, clinker or ceramic tiles. Of course, you can do without it, but it will contribute to a significant increase general aesthetics building.
The blind area around the house is important element construction of most buildings, and it cannot be ignored. Building a concrete blind area with your own hands is quite simple if you follow the step-by-step instructions and take into account all the recommendations. It is also useful to watch a video that clearly demonstrates each stage of creating a blind area.
Construction of the house has been completed, but the owners still have a lot of trouble ahead, primarily aimed at ensuring the safety of their new home. Building construction, no matter how durable they may seem at first glance, without proper protection they can suffer significantly from the effects of frost, snow, rain, and winds. This effect on the foundation is especially dangerous, because its deformation or partial destruction can negatively affect the strength of the entire structure of the house. As protective agent It is recommended to build a blind area around the house - it is intended to protect the foundation from the destructive effects of precipitation.
What is the blind area of a private house
The blind area of a private house is a strip of dense material, for example concrete or asphalt, which is adjacent to the foundation, protecting it from moisture. When laying the blind area, the slope angle recommended by building regulations must be observed, which allows melt or rainwater to flow freely; usually it is in the range of 10 to 15 degrees.
The recommended width of the blind area of a private house is from 0.8 to 1.2 - 1.5 m, it is located along the entire perimeter of the structure. It is difficult to overestimate the importance of a blind area for houses with a ground floor or basement: it not only significantly increases the strength of the foundation, but also helps create an additional insulating layer that creates a thermal cushion.
In addition to its protective functions, the blind area around the house helps to give the structure a more aesthetically pleasing and complete appearance. Practical owners resort to constructing blind areas not only around a residential building, but also around all kinds of technical and service premises, brick fences, built on the territory of the estate.
Types of blind area
In construction, it is customary to divide blind areas into three types:
- made from asphalt or stones
- classical
- monolithic.
Classic blind area usually has a width of 80 cm, is built along the entire perimeter of the structure, its slope is about 10 degrees. However, the width of the blind area should be chosen taking into account the protrusion of the roof of the house; at least 20 cm should be added to it. The width may also depend on the type of soil in the area where the house is located: the easier the soil is compressed, the wider the blind area should be made. If there is a basement in the house, it is recommended to insulate the blind area using heat insulating material.
It should be noted that the blind area, no matter what material it is made of, will be subject to destructive effects if the drainage from the roof is not done correctly or is missing.
Clay can be used as the basis for a classic blind area. The procedure for performing the work is as follows: a shallow (about 10 cm) trench is dug around the perimeter of the house, wet clay is poured into it and compacted tightly. After drying, the clay forms a dense mass that can provide the proper level of protection from moisture.
The boundaries of the blind area are curbs; they should be dug into the ground up to half the height.
On top of the clay layer, crushed stone of the middle fraction is poured and compacted tightly. Concrete or concrete is used as the last layer cement mortar, reinforced or monolithic, a composition of asphalt and artificial filler is often used. Using asphalt concrete, popular in urban housing construction, in a private home may not be practical: laying it requires the use of professional equipment and compliance with operating standards. In addition, laying asphalt concrete should be carried out at a material temperature of about +120 degrees and an air temperature of at least +5 degrees.
For styling stone blind area you will have to stock up on enough cobblestones and stones. In this case, the trench should have a depth of about 30 cm. Gravel is laid at the bottom of the trench, compacted, then clay is poured in and compacted. To provide protection from moisture, a layer of insulating material - roofing felt - is laid below and above the clay layer. Next, they begin to construct the decorative layer: selected stones are laid on the cement mortar.
Most quality option experts believe monolithic type blind area. A monolithic blind area at home can be done with your own hands if the owners are familiar with the technology for performing such work. In addition, it will require serious financial expenses. In order to fill the trench, only clean sand is used, it is compacted and filled with a layer of concrete 6 to 8 cm thick. The concrete must be of good quality and resistant to freezing. The structure must be strengthened with reinforcement laid on the base before pouring concrete.
We should also not forget about the need to create an expansion joint in the monolithic structure. For this purpose, carefully selected and treated resin and by special means board. Preference should be given to boards with a thickness of more than 15 mm. The expansion joint will prevent cracking of the monolithic coating and increase its resistance to mechanical loads with sudden changes.
How to properly make a blind area at home with your own hands
Now let’s look in detail at how to make a blind area at home using hand-made reinforced slabs. Making them is not very difficult. To create the slabs, you will need to make a formwork measuring 60x60 cm. It is recommended to make it on two slabs located next to each other. The height of the slab is 3 cm. The formwork boots are assembled in such a way that after hardening sand-cement mortar they were easy to take apart.
For increase quality characteristics It is recommended to reinforce the slabs; for a 3 cm thick slab it is very important to provide additional rigidity. Any mesh with a cell size larger than 8x8 cm can be used as a reinforcing component. Cells that are too large will lead to a decrease in the strength and rigidity of the finished product. Any material can be used as a reinforcing component. hardware, for example, a cable or wire, but always cleared of insulation.
After making the formwork, you can begin making the slabs. The base of the formwork will need to be covered with polyethylene. The film should be carefully leveled. Next, the formwork is filled 2/3 in height with a solution prepared from 3 parts sand and 1 part cement, the prepared reinforcing mesh is laid, and the rest of the solution is added until the desired height is obtained.
To improve the setting process, the surface of the tiles is covered with burlap. The formwork can be removed after 3-4 days. Slabs made in this way can be used even if the drainage is not properly organized. Plates laid on a prepared base will last a long period; moreover, their service life can be extended by periodically rotating the slab 90 degrees.
In addition, self-made slabs will help improve the area around the house and make it more decorative look: If desired, you can add dyes of different shades to the solution - the slabs will turn out colored.
Blind area made of paving stones and paving slabs
Today construction market filled with all sorts of varieties paving slabs and paving stones, their price is quite affordable, so often instead handmade slabs for blind areas resort to purchasing ready-made finishes. Industrially manufactured slabs have their advantages:
- they are very easy to install,
- if necessary, damaged fragments can be easily replaced with new ones,
- These tiles are resistant to high loads, exposure to moisture and low temperatures.
It is quite possible to construct a blind area at home with your own hands. In order for the blind area to last for a long time, you will need to properly prepare its base. A trench about 40-50 cm deep is dug around the house, a layer of drainage is laid in it: gravel, crushed stone, coarse sand with a thickness of 25 to 35 cm. The recommended slope of the paving slab blind area is from 5 to 10%, this is done at the installation stage drainage system. The minimum slope value is 1.5%, i.e. about 8 mm for every about.5 m of blind area.
A gap of a couple of centimeters should be left between the foundation and the blind area, otherwise when negative temperatures The tile, expanding, will create additional pressure on the foundation, which is extremely undesirable. The gap can be filled with sand or polystyrene and closed with several layers of roofing felt.
After the drainage layer, a layer of reinforced concrete is constructed, the dry mixture is poured, leveled and compacted, and tiles are laid on it. An attractive factor in the use of paving slabs can be considered the variety of their shape, size, and wide range of colors.
When choosing optimal option When making a blind area around the house, you should definitely take into account not only the financial side of the issue and external attractiveness finishing material In order for the blind area to serve for a long time, first of all, it will be necessary to take into account the peculiarities of the soil structure on the site, its geographical location, quality drainage system roofs of the house.
Today we will continue the topic of the foundation and plinth of your house, or rather, we will “close it” with an article about how to build a concrete blind area correctly and inexpensively with your own hands for your home. We will look at the simplest and inexpensive way devices concrete blind area(after all, our task is to build an inexpensive house with our own hands, which is not inferior in reliability dear home. Remember?).
So what do we have? The construction of our house is completed: the roof - it's all finished. It's time to start building the blind area. In fact, the blind area can be made almost any time after the walls are laid. But the most optimal time, in our opinion, this is when you start the final exterior decoration your house. If you plan to cladding the base, then the blind area should be done after this work has been completed.
Why do you need a blind area?
If you do not have enough funds for the final finishing of the house, then blind area We still recommend doing it. In any case, the blind area should be done before the cold weather. Then your house will “overwinter and welcome spring” without any problems.
And now - the main functions of the blind area:
- Decorative effect, a sense of architectural completeness;
- Except decorative element houses, blind area is protection of the foundation from external waters: melt water, rain. Retaining water and diverting it to the storm drain (this is what you plan to do) is the main task of the blind area;
- In addition, the blind area allows you to reduce freezing of the soil underneath it, and, accordingly, around the house. Those. the blind area guards the heat of the house;
- Reducing soil freezing entails reducing the likelihood of soil heaving. It is recommended to do this on swelling soils. True, we decided not to do this;
- If there is no blind area and the soil comes close to the base, then in addition to excessive moisture, plant roots can also cause damage to the foundation.
How to make a blind area correctly?
The simplest option is a concrete blind area with a width of 60 cm, which surrounds your house on all sides.
In order for the blind area to fully fulfill its purpose, it is necessary to follow several basic rules:
- the width of the blind area should not match or be less than the roof overhang. Minimum width of the blind area = roof overhang (eaves) + 20cm;
- the blind area should continuously encircle the entire house. Then the base of the house (and the basement) will be protected from moisture penetration;
- the wider the blind area, the better the function of protection against water penetration will be performed;
- the blind area must be performed with slight slope. The minimum slope from the house towards the ground, which will ensure water drainage, is 1.5 degrees. The slope may be greater. It depends on the base coating. The slope can be formed both at the stage of creating the underlying layer and at the stage of laying the coating. We will describe below what the underlying layer and coating are.
DIY concrete blind area
The durability of your foundation depends on the blind area, carried out according to all the rules, minimum expenses both money and time for repairing the foundation, basement and blind area and the absence of “headaches” after you have finished building your house with your own hands - and this is probably the most important thing!
The blind area is two structural layers:
- underlying layer. The main task is to create an even, compacted base for the coating. Material used: clay, sand, small crushed stone. The material for the underlying layer depends on the covering material. Thickness - up to 20mm;
- coating. The main task is water resistance and resistance to the destructive effects of water. Material used: clay (clay is a material that can be used as both an underlying layer and a coating), concrete, asphalt mixture, small cobblestones. Thickness - up to 10 cm.
This is true for any type of blind area. In this regard, we will tell you in what order the work should be performed for concrete blind area structures.
- We carry out markings for the future blind area. We talked about the minimum width of the blind area in this article above. The width of the blind area in our house is 100cm;
- We remove and compact the soil around the perimeter of the building. Usually the soil is removed at zero cycle construction. When constructing a blind area, you need to prepare the soil exactly for the width of the future blind area in accordance with the markings. In this case, you need to consider what material you will make the blind area from. For a concrete blind area, the soil must be removed to a depth of 20-25 cm - the depth “at the bayonet of a shovel”;
- Sometimes it is recommended to treat the roots of plants under the removed soil with herbicides, which can subsequently cause harm to the blind area. This is at your discretion - we did not do this;
- We make formwork from boards. For formwork we use boards 20mm thick. We talked about how to properly make removable formwork from boards (the principle is the same) in the article;
- Place a small layer of clay on the compacted soil. Level and compact the clay;
- We lay a layer of sand 10 cm thick. The sand must be thoroughly compacted. To do this, it is effective to shed the sand with a layer of water. Don't overdo it - there's clay underneath! Compact the sand especially carefully near the foundation.
- Now we lay crushed stone in a layer of 6-7 cm;
- To strengthen the blind area, we reinforce it with reinforcement mesh (see photo) in increments of 100 mm. It is typical for concrete to withstand compressive loads. Reinforcement allows the blind area to also effectively withstand tensile loads;
- At the junction of the blind area with the plinth, it is necessary to make a seam, which is called a compensation seam. It is also called deformation or temperature. The expansion joint will protect the base and blind area from destruction during soil subsidence. In this case, the blind area will sag or fall along the prepared seam without causing damage to the base. The width of the expansion joint is 1-1.5 cm. We fill this gap with a mixture of sand and fine gravel, bitumen, mastic or two layers of roofing material. Some builders use foamed polyethylene to fill the seam. The diameter of the tourniquet should be 25% larger than the width of the seam so that the tourniquet fits tightly into the gap. A special feature when laying a rope: its top should be at a depth equal to 1/2 the width of the seam. To make laying the bundle easier, you can use a piece of plywood. And although we talked about this method of filling an expansion joint, we did not use it ourselves. We used sealant;
- When pouring a blind area with concrete across the blind area, an expansion (temperature) joint should be constructed every 2-3 meters (the distance depends on the likelihood of soil swelling). Expansion joints protect the concrete blind area from possible ruptures in winter. Suitable for these purposes wooden slats, mounted on edge. The slats must be installed so that their top surface coincides with the surface of the concrete. IMPORTANT! Consider the slope of the blind area! To protect the slats from rotting, we treated them with waste oil (used oil). Wooden slats can also be processed;
- Expansion (temperature) joints must also be installed in the corners of the house;
- We put and ;
- Align concrete base. Wooden slats pre-installed to create expansion joints play the role of beacons that should be followed when leveling the concrete;
- It will give maximum strength to the formwork. Ironing done using the wet method will give the blind area for your home maximum moisture resistance;
- And the final stage: cover the concrete surface with a cloth, wetting it with water from time to time. This will keep the concrete from drying out until it is completely cured. If you are making a blind area during the rainy season, and this is exactly what happened to us, you can do without additional moisture. Daily rains will do their job;
- In a week, the correct concrete blind area for your home is ready.
Repair of concrete blind area
If you have properly completed the foundation, plinth and blind area for your home, you should not have problems for a long time.
However, it happens that cracks appear on the blind area or damage takes up a significant area. What to do in these cases?
- Small cracks should be filled with liquid cement mortar (1:1 or 1:2);
- More large cracks must be cut down to its full depth and cleaned of contaminants. Then fill the prepared cracks with mastic of the following composition: 70% bitumen BND-90/130 or BND-60/90, 10% crushed slag and 15% asbestos. Cracks filled with mastic should be sprinkled with sand.
- If the damage to the concrete blind area is significant, it is necessary to restore it with fresh concrete. To do this, clean the surface to be repaired from dirt and prime it. For priming, use cement mortar (1:1 or 1:2). Then lay fresh mortar and level it. Next, you need to prevent the laid concrete from drying before it hardens. In other words, periodically moisten it or cover it plastic film to prevent drying out.
IMPORTANT! It is more effective to repair the blind area in spring or autumn in cool weather. If you need to repair the blind area in the summer, choose the morning hours for this. During the day, under the influence of high temperatures, due to the expansion of concrete, the cracks will decrease. This will prevent you from completing your repair as efficiently as possible.
