Plate( floating) foundation with own hands

Plate foundation - one of the types of monolithic foundation, is a monolithic concrete slab laid on a prepared base of sand and gravel. Perform such a foundation mainly on weak soils: peat bogs, sands, saturated clays, prone to movement and whipping. The foundation does not penetrate to the depth of soil freezing, and with seasonal soil movements it evenly moves along with them. For this feature it is also called "floating".In this case, the structure does not experience point loads, all the shifts are transferred by the foundation to the walls evenly.

Scheme for installing the floating floating foundation

Features of the plate foundation

Advantages:

• As already mentioned, the slab foundation can be executed on weak soils with a considerable depth of freezing, without the need for a deep trench as for a buried foundation;
• The bearing capacity of the slab foundation is high, unlike the pile foundation, it can withstand considerable loads: the capital structures of blocks or bricks 1-2 storey high;
• The ability to withstand loads and shifts from the ground without deformations makes the "floating" slab foundation very durable, its service life is about 150 years;
• The foundation, thanks to its design, also serves as a rough floor for the basement floor, which allows to save a few on its device.

Disadvantages:

• The slab foundation is more expensive than the pile foundation due to the considerable consumption of materials;
• The high laboriousness of manual work and the need to use construction equipment make the cost of the slab foundation more expensive.

Workflow technology

1. Site preparation is the most time-consuming operation to perform a slab foundation. It is necessary to completely remove the upper layer of the soil to a depth determined by calculation. At the same time, the last layer should be removed and aligned manually, in order to avoid unevenness and pits: any depression, even covered with sand later, can serve as a cause of deformation due to uneven load during the operation of the house. The pit should exceed the dimensions of the foundation by 1-2 meters from all sides for the convenience of work.
   

   Site preparation process for the future foundation

2. The second stage is the preparation of a cushion of sand and gravel. It is necessary to compensate for the forces of deformation of the ground, as well as for abstracting groundwater and excluding their capillary rise to the foundation of the foundation. The thickness of the pillow depends on the characteristics of the soil: on sandy grounds, it can be 15 cm, on saturated clay, prone to strong puffing - at least 30 cm. The sand is poured into the prepared foundation pit, evenly distributed throughout the foundation area and carefully compacted. For marshy or humid soils, part of the pillow is made of crushed stone, this improves the waterproofing of concrete.
   

   Creating a cushion of sand and gravel for the foundation of

3. plates Formwork. Removable formwork is made of planed boards with a thickness of at least 20 mm, fastening them to the corners using self-tapping screws. On the outside, the formwork must be reinforced with struts. It is possible to use a non-removable formwork made of fibreboard. It is attached to metal corners and ties, and then they also arrange struts. Arrange the penetrations for communications, carrying out around them formwork. Pipes can also be laid and taken out through the penetrations before the foundation is poured.
   

   Formwork under the foundation

4. Waterproofing is produced with the help of a thick polyethylene film, geotextile or roofing material, laying it overlapping the bottom of the excavation with the approach to the formwork. Reinforcement of the foundation is a very important stage, the strength of not only the foundation itself but also the building as a whole will depend on it. For small buildings, it is possible to produce reinforcement with reinforcing mesh with a mesh of 10-15 cm, and places, and which will be supported by walls, must be reinforced with a metal rod. If the structure of the building is more massive, for reinforcing it is necessary to use a rod with a diameter of 10-12 mm, laid in the form of a grid. Transverse rods are knitted together by wire. Welding of the reinforcement is not recommended, since excessive stresses occur in the welding places during structural motions. The reinforcing mesh must be completely immersed in concrete, so install it on special guides. If the thickness of the foundation is significant - install several layers of reinforcement.
   

   Foundation waterproofing process

Reinforcement of the foundation is a very important stage, the strength of not only the foundation itself but also the building as a whole will depend on it. For small buildings, it is possible to produce reinforcement with reinforcing mesh with a mesh of 10-15 cm, and places, and which will be supported by walls, must be reinforced with a metal rod. If the structure of the building is more massive, for reinforcing it is necessary to use a rod with a diameter of 10-12 mm, laid in the form of a grid. Transverse rods are knitted together by wire. Welding of the reinforcement is not recommended, since excessive stresses occur in the welding places during structural motions. The reinforcing mesh must be completely immersed in concrete, so install it on special guides. If the thickness of the foundation is significant - install several layers of reinforcement.

Foundation reinforcement process

The concrete is poured concurrently, so the concrete must either be ordered or mixed very quickly. Therefore, the fill should be made by a team of 4-5 people. Concrete is poured into the prepared formwork with the laid reinforcement, then it is compacted first by means of a deep vibrator, and then using a vibrating rod. After punching the concrete and removing voids and air from it, it is smoothed and its surface leveled.

Dry the foundation for 4-5 weeks. During this time, concrete is gaining the necessary strength, after which it is ready for further construction. During drying, you must ensure that the top layer of the foundation does not dry out and is not waterlogged, it is convenient to use the covering material for this. After the concrete dries to improve its thermal insulation properties, the slab foundation is insulated with polystyrene boards.

Ready-made slab foundation

A slab foundation is often used in the construction of private houses. Its design, for all its laboriousness is quite simple, so you can perform a solid foundation with your own hands, attracting special equipment only to particularly critical or hard work.

In conclusion, we advise you to read also about: the foundation of asbestos-cement pipes, and how to make a bored foundation with your own hands and of course read how to insulate the foundation.