Good afternoon, dear guests and subscribers of the "Build for Myself" channel!
Building codes and regulations in construction provide for the use of various types of foundations, including shallow foundations (FMZ). This phrase itself says that the depth of the bottom of the foundation (the base of the foundation) is located shallow from the soil surface and is in the zone of soil freezing.
Shallow foundations are divided into structural types, they can be either columnar or tape or slab.
But, precisely when choosing the type of foundation - FMZ, you need to understand that such a structure should have excellent strength over the entire area, good resistance to overturning and sliding.
In addition, the soil located at the base of the base of the foundation must be protected from the forces of frost heaving, which is achieved only by using various types of insulation. Both the foundation itself and the blind area of the house are insulated (figure below). Neither a sand cushion nor crushed stone bedding will cope with the task of compensating for soil heaving, all such options have already been tested a thousand times. Frozen soil under various beddings raises both sand and gravel, and together with them - the whole house.
Often from the builders you can hear "Yes, we will make a porch for you in 2 days, fill the shallow slab with steps and you will be happy." This is a completely wrong decision! The foot of the porch foundation must always be below the frost penetration mark. Always! And that's why...
When the shallow foundation of the house is insulated, the insulation saves the soil under the foundation from freezing. And he saves only thanks to the positive temperature inside the house! Because, by itself, the insulation does not emit heat and this factor is the basis of insulation systems.
The insulation retains the temperature around the circuit, but itself is not a producer of either heat or cold. Around the refrigerator - it will keep cold, in a thermos - it will keep warm.
Now about the porch. It is always on the street. Around the porch, at least from 3 sides of it, it is always frosty. There is no system that would radiate heat into the porch, and since there is no heat carrier, the insulation does not work. He has nothing to hold back!
Therefore, under the porch in winter, the temperature is always negative, and this is a fact. Frost also spreads into the ground up to the frost-free border. That is why it is for the porch that you need to lay the foundation below the freezing mark.
If you don't want to spend money on the foundation, there is a budget option :-))) Here is a link to my article: Concrete CONSOLE porch without foundation (This worthy and reliable solution will last for years)
That's all. Hope this article was helpful to you!
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