Pouring a concrete blind area around a private house

Concrete blind area is an important element of the house. Often this construction seems insignificant, but if you look into the matter, it is very important. It is necessary to follow the technology and choose the right type of construction. How to fill the blind area yourself around the house, is described below.

What is she for?

Concrete pavement is a must. Its device performs a very important function - the protection of the foundation. This element around the house removes rain and melt moisture from the perimeter of the basement walls, which reduces the load on the drainage system and vertical waterproofing.

Before you make a blind area with your own hands, you should decide on its width. To perform a given function, its protrusion of the blind area around the house is taken equal to one meter. This value allows you to reliably protect the walls of the basement. In some cases, it is allowed to reduce the width, but only if absolutely necessary (for example, tight conditions on the site). The minimum value is 80 cm. It is important to take into account the protrusion of the roof eaves. Its projection on the ground surface must be at least 20 cm less than the protrusion of the concrete protection.

The main role of the blind area is to protect the foundation from water

In addition to waterproofing, the blind area takes on several more functions:

• completion of the architectural appearance of the house;
• arrangement of a pedestrian zone around the building (the blind area plays the role of a footpath).

It is possible to use the blind area as a path only for low-rise individual buildings, provided that ice is removed from the cornice and snow from the roof in a timely manner.

To perform the main function - the flow of water, the blind area must be made with a slope. The decrease in height occurs away from the walls of the house.

The blind area around the building assumes a slope of at least 0.015.

This value means that for every horizontal meter there is a vertical change of 1.5 cm. Before pouring the blind area, you should calculate its height at the walls of the house.

The design of the blind area and materials

The concrete pavement is arranged quite simply. Filling the blind area around an individual house is within the power of even a non-professional. The device requires the preparation of the following materials:

1. Adding, which must be done before pouring the solution with your own hands. You can make bedding from various materials. The design allows the use of medium or coarse sand, sand and gravel, crushed stone or gravel of a not very large fraction. Do not pour cement mortar over fine sand. Such a base can shrink, which will cause the concrete for the blind area to crack. It is best to make a pillow from two types of material. The first layer must be done in order to compact the base soil and level it. To do this, use gravel or crushed stone. Make the second layer of sand.
2. To increase the strength, pouring the blind area involves reinforcement. You can make reinforcement of the element around the house with your own hands using reinforcing mesh. It is recommended to make meshes from reinforcement with a diameter of 6-8 mm, depending on the characteristics of the base soil. The blind area device assumes the size of the grid cells 30x30 or 50x50 mm.
3. Before pouring, it is necessary to make formwork. It is necessary to make wooden shields around the perimeter of the blind area so that the concrete solution does not spread. For the manufacture of formwork, wooden boards will be needed. The width is selected depending on the thickness of the blind area. To keep the solution, it is enough to purchase material with a thickness of 22-25 mm.
4. The main material for the manufacture is concrete mortar. The most important thing here is to choose the right brand of mixture. The strength class of concrete must be at least B15 (old marking M200).

You can use a solution of higher grades, but this is not profitable from an economic point of view. To make a durable building element, you also need to think about frost resistance. The grade of concrete for the blind area in terms of frost resistance must be at least F50. It is best to make a choice in favor of the F100 brand, such a solution will provide the best resistance of the element to temperature extremes. When preparing concrete, it is important to observe the proportions of its components.

The composition of concrete for the blind area

To do high-quality work with your own hands, you will need to correctly select the concrete mix. There are two ways to get a filling solution:

• purchase at the factory and transportation by concrete mixer;
• self cooking.

It is better to opt for the second option. This is due to the following factors:

• buying a ready-made mixture is always more expensive than making it yourself;
• a small amount of concrete is required for the blind area, and factories sell it in fairly large volumes;
• no need for transportation costs.

The home master in the manufacture of the mixture should only correctly select its components and observe the proportions. The composition of concrete for the blind area is as follows:

• cement (it is better to use PC400);
• sand (the best option is medium, fine is allowed);
• coarse aggregate (crushed stone or gravel);
• water.

The proportions of each of these components are set depending on what brand of concrete you need to get. For concrete grade B15 (optimal for the blind area), the proportions must be done as follows:

• cement -1 part;
• sand - 2.8 parts;
• coarse aggregate - 4.8 parts.

These proportions from 10 liters of cement make it possible to obtain 54 liters of concrete mix. For every 6 parts of water by weight, there should be 10 parts of cement.

If you need to create a material of a different brand and there is no way to more thoroughly familiarize yourself with the information, you should remember that in general the proportions look like this: 1:3:4 (cement: sand: crushed stone, respectively).

Work order

The do-it-yourself device involves performing actions in the following sequence:

• first you need to mark the blind area on the ground;
• digging a trench along the perimeter of the building to the depth of the blind area (depending on the thickness of the layers of backfill and concrete);
• tamping the base;
• installation of formwork panels and fastening them together;
• laying of bulk materials (sand, crushed stone) with compaction;
• laying of reinforcing meshes;
• installation of boards that will play the role of expansion joints that prevent concrete from cracking in winter) in increments of 2 meters;
• concrete laying and compaction, leveling;
• surface ironing;
• waiting for time to set strength, concrete care.

It is important to ensure a distance of approximately 2 cm between the blind area and the wall. This gap will allow structures with different weights to settle independently of each other and prevent cracks from appearing.
Concrete gains full strength in 28 days at an average daily temperature of +20 degrees Celsius. If the air temperature is lower, more time will be required. The formwork can be removed after reaching 70% strength.

Care of concrete consists in its periodic wetting. To prevent evaporation of moisture, the blind area after pouring is covered with a film or burlap. These measures will prevent the appearance of cracks during solidification.

An additional measure may be the insulation of the element. To do this, use extruded polystyrene foam, which is placed under a layer of concrete on a backfill. Warming is relevant when the depth of the foundation sole is higher than the freezing depth.