The foundation is the basis of all buildings and structures. This is the name of the building structure that takes on the entire load of the building. The strength, reliability and durability of the structure erected on it depend on a correctly calculated and competently laid foundation. Therefore, its construction should be taken with full seriousness and responsibility. This article touches on the topic of building a foundation with your own hands with step-by-step instructions.
Varieties of used foundations
Today, there are several types of foundations, which differ in the method of laying and constructive solution. Among them are:
- columnar;
- ribbon;
- pile;
- floating;
- screw;
- shallowly buried.
Let's consider laying a strip foundation with our own hands.
Strip foundation
This type of base is one of the most common. He is characterized by:
- significant weight;
- labor-intensive work;
- high consumption of materials.
But its use is possible for the construction of heavy walls using bricks, cinder blocks, foam blocks. For covering with concrete slabs, which significantly increase the overall weight of the building.
The strip foundation is a reinforced concrete strip closed along the contour, along the entire perimeter of the building and the provided partitions. To build a foundation with your own hands, you must, first of all, calculate it correctly.
Calculation of the strip foundation
In order to make the correct calculation, you need to have some parameters. The total length of the tape (calculated by adding all the individual sections along the perimeter with sections of the walls), width and height.
All these data must be specified in the project drawn up for construction. If the construction is not complicated and a small house is being built from the foundation to the roof with your own hands, you can calculate everything yourself. It is easy to find out the total length with the help of a long tape measure. When choosing the height of the foundation, general recommendations should be taken into account: the depth of occurrence should be 20-25 cm below the freezing point of the soil, but not more than 50-70 cm from the ground level. The height above the soil level depends on the terrain, the design of the future structure and is chosen by the developer. The width of the foundation depends on the wall construction materials and should be wider than the thickness of the walls.
Preparation of foundation pit
The next step when building a foundation with your own hands is to mark the future pit onterrain. To do this, use a long cord, tape measure and a tool for measuring angles. Pegs are hammered around the perimeter, a stretched cord is attached to them. Digging the foundation can be done both with the use of earth-moving equipment, and manually, with shovels. The second method is more laborious, will require more time and physical costs, but is cheaper in finance. This is how a foundation pit is dug, the bottom and walls are manually leveled.
Formwork
The most important stage in the construction of a strip foundation with your own hands is the assembly of the formwork. A formwork is a structure for holding a solution in a certain form: cement and sand (concrete), until it is completely solidified. Various materials are used for its construction: wood (board, plywood, OSB), metal sheets, polymer, plastic.
The entire structure inside can be lined with a film or special lubricants so that the solution does not stick to the walls. This makes it easier to remove structural elements. A frame of reinforcement is placed inside the formwork. It is designed to bond concrete from the inside. It is considered correct to manufacture a frame by twisting reinforcement elements with wire. Welding is contraindicated. This is due to the expansion and contraction of volume with temperature changes. A welded structure can be torn, while a twisted one will "breathe" at the place of twisting.
Preparing and pouring the solution
The next step in creating a foundation with your own hands is preparing a mortar(concrete mix). Concrete is a liquid mixture of sand, crushed stone, cement and water. To prepare it, you will need a concrete mixer with an electric drive. Mixing the solution in such volumes by hand is simply unrealistic. Components in a ratio of 1:3:5 (cement, sand, crushed stone), i.e., 30 kg of sand and 50 kg of crushed stone or gravel are taken for 10 kg of cement. Cement grade not lower than 200 is used. The number in the grade of cement means the bearing load per cm2. So, for example, using cement grade 300, the foundation can withstand a load of 300 kg/cm2. Only fresh cement should be used for mortar, given that during storage for 1 month it loses its strength by 10%, in two months, respectively, 20%.
All components are loaded into a concrete mixer without adding water and thoroughly mixed in dry form until a homogeneous mass is obtained. After that, water is added and the composition is brought to the consistency of sour cream. The solution should not be very liquid and excessively thick. Ready concrete is poured into the formwork, filling all its space. For high-quality pouring and preventing the formation of voids (otherwise the foundation made with your own hands will not have sufficient strength), a deep vibrator is used.
Vibrator for foundation compaction
In the process of preparing the concrete mixture and pouring the formwork, air bubbles are obtained. They can range from small to large voids. Given the high density of the cement slurry, these bubbles cannot come out of the slurry on their own. For thisthere is a special device - a vibrator, the use of which accelerates the process of shrinkage and compaction of concrete. Vibrators are produced by the industry powered by electricity and liquid fuel. The use of the device on gasoline is possible at facilities where there is no electricity. The use of such devices contributes not only to the removal of air from the solution, but also to an increase in the rate of hardening of concrete due to the removal of excess moisture from its composition during shrinkage. In order to make it easier to lay out the first row of walls horizontally in the future, the pouring is done by leveling the top of the foundation along a cord stretched strictly horizontally.
Exposure of poured foundation
It should be noted that the foundation for a house with your own hands, as a rule, is performed in the warm season. In dry and hot weather, the poured solution is covered with rags and periodically, as it dries, watered. Humidification is necessary in order to prevent the rapid evaporation of moisture and the drying of the foundation of the house.
If necessary, filling is allowed in the cold season, even in frost. But in this case, it is required to mention some features of building a foundation with your own hands. When cold, the water in the concrete will freeze and will not perform its functions. Cement must stand, seize and harden. In frosts, you will have to apply heating of the foundation in any way (wrapping, steam, building tents with heating by a potbelly stove, stove, firebox). This, of course, is a long and energy-consuming process, but, if necessary, winter construction, without thisindispensable.
After pouring, the foundation must stand. The term depends on its depth. The greater the depth, the longer the curing time of the concrete. This will take about a month. The poured foundation shrinks intensively for the first month, then, during the year, it also changes, but to a lesser extent. These transformations cannot greatly affect the state of the building.
Pillar Foundation
Another variety is a columnar foundation. From the name it is clear that it is a group of concrete columns on which the entire building is based. The area of support of such a foundation is rather small, compared with a tape or tiled foundation, respectively, a smaller load is allowed on it. This foundation is well suited for building houses that do not have a lot of weight. These are wooden log cabins, frame houses, using plywood or OSB sheets.
Despite the disadvantages, this foundation has a number of advantages. As you know, any type of foundation must be based on solid ground. This is his purpose. A situation may arise when there is loose soil on the surface, and solid layers are located at a certain depth. This is the reason for the use of columns. It is convenient to use the base in the form of them when building objects on sloping terrain, when the use of a tape support is impractical.
You can not use such a foundation with a high level of groundwater. It is not possible to rely on layers of earth with high humidity with the help of columns. Wells drilled for the foundation will be filled with water, this is unacceptable. A house built on a columnar foundation cannot have basements. Nevertheless, such foundations find their use.
Pillar foundation installation
Do-it-yourself columnar foundation is troublesome, but quite real. To begin with, it is worth understanding what kind of design it is. As mentioned above, this is a system of pillars made of various materials, arranged in a certain order. To lay the foundation with your own hands, step-by-step instructions provide for the need to mark the location of each of the pillars on the ground. The upper end of the support is called the head. The bottom of the building will be laid on it. The lower part is the base. It rests on the ground. The pillars are primarily placed around the perimeter of the base, its corners and at the intersections of the walls. Considering that the base of the house will be installed on the heads, they should all rise to the same height. If the terrain is uneven, you can align them with each other using a cord and a level. Post shape:
- square;
- round;
- rectangular.
The most common are poles with a round cross section. Under such structures, it is possible to prepare wells even with the help of the simplest home-made hand drill. Speaking about the foundation with your own hands, the instruction provides for the material used to make the support pillars. These can be logs pre-impregnated with a composition that prevents the penetration of moisture into the wood. You can use brick andmonolithic concrete.
The height of the pillars above the ground is determined by the height to the first floor. Usually, this is up to 50 cm. Such a gap is needed for ventilation and prevents dampness in the wooden structures of the lower part of the building. Indeed, on such a foundation, a wooden structure is usually built.
The best, no doubt, can be called a monolithic reinforced concrete version.
A frame of reinforcement is placed in the prepared well (following the example of a strip foundation), the formwork is raised to the ground level and poured with the prepared concrete solution. Shrinkage is done using a vibrator. Reinforced in this way, a monolithic pole has high strength. Internal reinforcement with a rebar frame makes it resistant to temperature extremes and other natural phenomena (rain, snow, wind).
In conclusion
In conclusion, I would like to note that building a foundation with your own hands is available not only to professional builders, but also to ordinary developers. Here is a step-by-step instruction only for certain types of foundation, while there are many more, but the use of any of them is equally important for the construction.
