Check the soil
Before starting work it is important to check the soil for its compliance with the type of foundation being built. It is quite simple to do this: it is enough to dig a small depression in the place where the foundation pit will be erected, in which case you will be able to evaluate the composition of the layers. If you notice viscous or soft soils (garden, forest land), then this will not be a good option. In such a place, construction costs may increase significantly.
If you find in the composition of the soil gravel, sand, well-established or compacted foundations of the previous house, loam or clay, then this soil is a more suitable option. In case, if you find a ground of gravel, untouched sandstone, untouched rock, a meter thick and more, then this will be an ideal place to build a house. The main thing is that under the foundation of the foundation the soil should be of uniform density.
Among other things, when examining the soil, it is important for you to check the depth of its freezing. After all, the depth of the foundation that is being built under the house will depend on this. The foundation must be laid to a depth lower than the depth of soil freezing, that is, it is 80-100 cm.Also, the depth of building a foundation for a house depends on the depth at which the groundwater flows.
If the level of freezing at the site of the future home is two meters above the groundwater level, then the foundation should be laid to a depth of 0.5 meters. If the groundwater passes in your area at a depth of less than two meters, then the foundation of the house should be laid at 0.5 m of freezing depth, but in this case a sand and gravel pad should be used. Since the ground will not freeze through the building, the foundation under the internal capital walls can be laid to a depth of half a meter as well. In this case, the level of freezing does not matter.
Before building a foundation, you need to remove 20-30 cm of the top layer of soil, level the surface, and clear the entire area under the future structure. Next, you need to mark the boundaries of the house, retreat a meter and score three racks in the corners. Horizontally, boards should be nailed to them, tied cords to the boards and tensioned. This mark means the red lines of the future home. And after all these manipulations, you can begin to dig a pit.