Finely stripped ribbon foundation with own hands

In a private low-rise building, the shallow-landed strip foundation is used as the most economical and, moreover, reliable construction solution. This type of foundation combines a number of advantages inherent in buried and unclouded grounds, so its use is widespread.

What is the difference between a shallow foundation and a foundation?

For the foundation of a buried structure, a foundation pit is required below the freezing level of the ground. In areas with severe winter, this depth exceeds one and a half meters, so without heavy equipment on the site can not do. The shallowly recessed ribbon foundation is a base made around the perimeter of all load-bearing walls, with the depth of the structure usually not exceeding half a meter.

The merits of a shallow foundation are:

• Simplicity of execution and low cost of work;
• Ability to build a foundation without the use of construction equipment;
• Strength, sufficient for the construction of small houses, baths or frame structures;
• Possibility of warming the basement;
• A wide range of materials and technologies for its construction: it can be monolithic, made with concrete pouring, and also composed of concrete blocks or bricks.

Among the shortcomings, it should be noted its inadequate strength for buildings built on the puddles. This problem can be solved by the device of sandy dumping and drainage, which will reduce the load from the ground.

The shallow foundation shall not be performed on frozen ground, or left unloaded for the winter, so the time for pouring the foundation and the construction of the walls is quite compressed and is in the middle band of 4-5 months.

Materials for the implementation of the shallow foundation

The simplest and quickest way to make a shallow foundation is to pour a monolithic base of concrete. However, it is possible and options: the foundation can be made of concrete blocks or a foundation of brick.

For monolithic foundation use concrete of brand not lower than 200, as well as reinforcement from metal rod D12-D16.Pouring is made either immediately, or by horizontal layers, there should not be vertical joints in the foundation - this will lead to its destruction.

If concrete is prepared independently, and large volumes can not be cooked at once, you can make a shallow foundation of concrete blocks made by yourself.

Technology for the implementation of a monolithic, shallow foundation

1. Remove a fertile layer of soil from the site and produce markings using pegs and kapron twine. Carefully measure the corners, check the distance between the walls with the project. By marking out a trench up to 70 cm deep. At the same time, it is necessary to start from the lowest angle of the section, and to level the horizontal plane of the trench along it. The walls of the trench must be strictly vertical. If the soil is loose, you can install supports.
   

   Preparing the foundation soil and restricting its territory

2. Geotextiles are laid on the bottom of the trench - a construction fabric that passes water, but prevents sand particles from entering the sand. The geotextile is laid in such a way that its edges are higher than the planned sandy backfill.
   

   We lay the geotextile

3. on the bottom of the trench. The bottom of the trench with the geotextile laid is covered with large sand. Backfill is done layer by layer, while each layer is spilled with water and compacted. The height of the sandy subsoil depends on the type of soil. On sandy soils it is enough 20 cm of sand, on saturated clay, its layer should be half a meter.
   

   Make a sand pillow on the bottom of the trench

4. . Over the trench, set the planking from the boards, continuing the walls of the trench. The boards are fastened with nails or self-tapping screws, while avoiding the nail ends protruding into the formwork, otherwise the formwork will then be difficult to disassemble. On the formwork on the inside, marking the level of concrete pouring is done. When performing markup, use the building level.
   

   We make wooden formwork for the foundation on top of the trench

5. . In the prepared formwork we lay the reinforcing bars. The metal rod is cut to the size of the walls in longitudinal and cross-section, and with the help of knitting with wire fasten them to the reinforcing bars. All the corners and joints of the walls must be tied with perpendicular reinforcement bars - this will preserve their tensile strength when moving the soil. If the height of the foundation is more than 30 cm, several layers of reinforcement are needed. Welding during the fastening of the rod can not be used for several reasons: there is a corrosion-unstable region at the welding site, in addition, the hardened rod loses its tensile strength during the welding process and can burst during operation. As a result - a crack in the foundation, gradually transferred to the wall of the building.
   

   The process of reinforcing a shallow basement foundation

6. Start casting the formwork with concrete. Fill the first layer and evenly distribute the concrete on the formwork, punching it in several places with a rod to remove air voids. Each subsequent batch of concrete must be poured before the previous one is seized, so it is better to fill it with a large brigade. The most recent layer is aligned to the markings, smoothed out with the rule and sprinkled with dry cement with a sieve - this measure leads to a more firm grasp of the top of the foundation and prevents the appearance of cracks when it dries.
   

   The process of pouring formwork with concrete

7. Maturing of concrete lasts 28 days and depends on the weather conditions. In this case, the construction of light buildings can begin in a couple of weeks, for the construction of a brick house will have to wait for the entire maturation period.

Technology of making a shallow foundation of concrete blocks

This technology allows you to perform a shallow foundation in stages, which is important for the construction of the foundation with your own hands. In this case, the concrete blocks can be made independently.

1. The form for the blocks is made of plywood in the form of a rectangular frame with walls, but without a bottom, while it is more appropriate to do it for 4-6 blocks, separating the structure with removable partitions. All parts are impregnated with engine oil - this facilitates the extraction of finished blocks. The bottom is a smooth surface, covered with polyethylene.
2. Mix concrete: take 1 part of cement, 4 parts of sand mixed with rubble, expanded clay or other filler. If desired, you can add fiber. The resulting dry mixture is poured with water and mixed, the resulting concrete should be thick enough, but free to fit into the mold.
3. Fill the mold halfway and lay the cut reinforcement mesh. Fill the mold completely, leveling the surface of the concrete. You can make blocks and hollow if you insert glass bottles into the mold.

The products are dried for 2-3 days at a plus temperature, after which they are removed from the mold and dried for another 2 weeks.

Laying the foundation as a whole does not differ from the monolithic one, the only difference is that the formwork is not performed above the ground surface, the monolithic base is filled from concrete in the ground, reinforcing it with a rod, and the ground layer is laid out of concrete blocks in several rows, using ordinary mortar for masonry.

A shallow strip foundation to improve its strength and thermal insulation properties, it is necessary to insulate, and also perform a blind. Warming is done from the outside with the help of polystyrene plates, it is also possible to spray polyurethane foam. Such a foundation is not afraid of seasonal soil movements and serves as a reliable basis for the structure. Also, we recommend reading about the monolithic foundation with your own hands.