Drilling in the strip foundation. Close in winter or not

How to make fictions (outlets) for ventilation of the foundation

Fiction in the foundation is needed so that the gap under the floor of the first floor is ventilated, for this special holes are made in the basement of the ground part of the foundation.

Lecture Foundations

Such ventilation is necessary, since moisture emerging from the ground can accumulate under the floor. This can lead to the fact that the building structures will be under constant influence of moisture, especially since it will constantly accumulate. This problem is very relevant when used during the construction of wooden structures. With increased humidity, rot and mold can defeat it, as well as formation on wooden structures of the fungus. In addition, radioactive gas of radon can be intended in the underground.

In the winter, the concentration of moisture and gas rarely increases due to the action of low temperatures, since the probability of evaporation is reduced, and are able to freeze on building structures, remaining, as it were, in a mothballed form until the next increase in temperature increases. To get rid of such a serious problem, in the ground part and make such holes.

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Do you always need torture in the foundation? No not always. These holes are made only in cases when there is an underground space. If your floors of the first floor are made on the ground, then you do not need to do the ventilations.

Why is the foundation ventilation needed

From the lack of ventilation of the foundation, the basement is first spoiled. Humidity grows in it, the liquid accumulates on the walls, ceiling ceiling, the flooring penetrates the floor. Due to the high temperature in the house, wet and warm materials in the basement become a place of propagation of bacteria, pests, mold. This leads to the appearance of unpleasant odors in the house, which will be very difficult to get rid of. The floors rot, their service life is reduced. In addition, the inhabitants of the house may be allergic to the fungus or mold.

The mold in the basement also accumulates GAZ Radon, which is released from the soil. This is a radioactive substance that very quickly penetrates from the basement into residential premises. In large quantities, it is harmful to the body-increases the risk of lung cancer, negatively affects the cardiovascular and circulatory system. In conditions of poor ecology, radon significantly reduces the quality and expectancy of life.

Water flow into the basement, the main reason for increasing humidity

What are fools

These are small through holes made in the foundation, or, in other words, outlets. Their shape can be any. round, square or rectangular. They are made at the stage of filling or building a strip base, but it is permissible to create them after the construction of the building, which, however, requires more effort than with their original design.

Since they are outlets for ventilation of the foundation, their purpose is to remove the water vapor from the basement, which is released from the soil or condenses due to the temperature difference inside and outside the construction. Steam can also be distinguished by vegetables stored in cellars. plants breathe. The moisture is especially actively condensed on the foundation walls and the lower part of the floor overlap in the cold season.

Condensate leads to an increase in microorganisms, many of which negatively affect the well.being of people living in the house, which entails an exacerbation of existing diseases and the emergence of new ones that can become chronic. Excess humidity leads to the destruction of building materials, especially in wooden buildings.

Fictions in the strip foundation are necessary so that air exchange is created between the underground and the external environment that helps to drain the basement and prevents the premature decay of building materials. Properly organized production of producers significantly extend the life of the house and positively affect the home atmosphere.

In what cases do you need to do them

Thus, you still need to make purges in most cases. This is stipulated even in regulatory documents. SNiPs. The exception is houses built using new technologies that came from Europe and America, in which underground is thoroughly isolated and falls asleep, which eliminates dampness and heat loss.

Arrangement of the thoughts in the built building

The house is already standing, but they forgot about the need for fictions? Everything can be fixed!

You need to perform one of two options.

  • Cut them yourself. This requires a disk with diamond spraying. Calculate and mark future. Cut holes, the parties will remain absolutely even.
  • Call specialists. They will perform all the necessary calculations on their own. The financial issue will depend on the thickness of the foundation and material of which it consists.

Do not require fictions if the floor on the ground floor is not overstated, but is equipped directly at the ground level. There will be no moisture under it, and the operational properties in such buildings are much higher.

Having correctly calculated and build a ventilation system of the basement, you can avoid many serious problems, thereby extending the life of the building as a whole.

In what cases do you need to do them

Often inexperienced builders do not know whether it is necessary to make purges in the strip foundation.

  • The space under the floor will not be stuffed with sand and waterproof;
  • The floor does not close the floating or hanging monolithic plate;
  • It is not planned to create forced ventilation;
  • The basement will be organized by storage of products.

Thus, you still need to make purges in most cases. This is stipulated even in regulatory documents. SNiPs. The exception is houses built using new technologies that came from Europe and America, in which underground is thoroughly isolated and falls asleep, which eliminates dampness and heat loss.

Rules for the organization of ventilation

The strip foundation with an air exchange calculated by the area of ​​air exchange, with an additional exhaust riser equipped with an additional option, this is the best option for equipment of the ventilation system for any basement. It allows you to completely remove excess moisture, dry all the structural elements. To achieve such a result, you need to follow a number of steps to design and implement the system.


How to calculate the required number of outlets in the foundation? You need to familiarize yourself with SNiP 31-01-2003. It indicates how many fictions you need to place per unit of the basement volume. So, according to the norms for 400 m 3 rooms, one ventilation hole is needed. If the region refers to the climate with high humidity, then the calculation of the fictions goes for every 150 m 3. Online calculator is used to simplify calculations.

In addition to externally bred flesh, it is necessary to provide ventilation holes in the pieces. To do this, you can make one large or several small holes.

Interesting! Sometimes, for better ventilation, ventilations are made not only in the walls of the foundation, but also the outlets are laid in the floor, thus providing better mixing and excretion of air masses.


When designing a house, the communications scheme should include the location of the fiction in the foundation. over, their distribution is based on the technological rules:

Stepped Strip footing

  • The holes of the outlets should be located equidistent from each other around the entire perimeter of the external walls. In this case, the distance between the two neighboring openings should not exceed 3 m.
  • For better drainage of wet surfaces and removing musty air, the vents should be as close as possible to the corners of the building. At the same time, it is worth calculating the number of fictions in one row so as to leave a distance of about 90 cm from the corner along the inside of the basement.
  • The location of the Undress relative to the floor and the surface of the Earth is also important to correctly calculate. Recommended distance: the middle between the soil level and the floor level. At the same time, the minimum distance from the Earth, at which rainwater and wastewater will not flow into thoughts. 20 cm. Important: to make strangles as high as possible, as far as the design allows.
  • To ensure good circulation of air masses, the holes of the fictions should be located symmetrically on opposite walls and in even quantities.

Shape and area of ​​holes

The construction standards do not indicate the requirements for the form of fragrances in the foundation. They can be any: round, square, rectangular, triangular. depending on the desire of the owner. However, most often during construction use round or rectangular ventilations.

The optimal dimensions in the foundation:

drilling, strip, foundation, close, winter

According to the norms, the area of ​​the opening of the Underwheel can reach 0.85 m 2. If the hole is planned, then it should reinforce it. Developers prefer frequent installation of small fictions, as they are more aesthetic in appearance. The main thing is to ensure the total area of ​​the holes corresponding to the needs of the air exchange. How to calculate? Again, contact the online calculator or use the services of an architect.

At what stage of construction are created

It is best to make a lot when the concrete base is poured. There are several options for their arrangement.

The method of past generations. With the help of a wooden beam, the base for the hole is collected. This design is attached with wire to the rods of reinforcement. The length of the wooden part should correspond to the width of the formwork. Когда бетон залили, он подсох, дерево вынимается, и на его месте остается сквозное отверстие.

This method has a number of disadvantages: due to the high pressure of concrete, the workpiece may be deformed; After the solution dries, it is difficult to pull out the bars sticking to it (use chisels, sledgehammer, drill).

Modern method. A piece of plastic or asbestos.cement pipe is used as a workpiece. Its length should also correspond to the width of the formwork. In order to prevent its destruction under the influence of a concrete mixture, sand is covered inside, and the edges are closed with wads. Such a workpiece is attached to the reinforcement wire. After the concrete dries, the wads are taken out and the sand is poured out.

Attention! There is no need to get the pipe from the walls, as it provides additional protection against moisture.

Is it possible to make in a finished foundation

Sometimes it happens that before pouring the foundation, blanks were not installed for deceit. What to do in this case? Often, after pouring concrete on the surface, a base is erected, which is a leveling layer for moving to laying walls. Then, when laying it, you can leave the required amount of rectangular outlets.

If the base is not supposed, then the exit will be the drilling of the foundation tape. How to drill strangers in concrete? To do this, prepare a diamond drill, a crown with a diameter of 100 mm (since a diameter of 110 mm is recommended in the standard). Before drilling, you need to mark the location of the holes in accordance with the project drawing. The main complexity of this method is not to hurt the rods of the reinforcement. You can make holes in the foundation with your own hands. But it is best to call a specialist for these purposes.

When there are no outlets in the foundation for a wooden house, you can drill them in wood, at the basement level. You need to mark the location, and then make a hole in the lower row of logs with a saw. Then the prepared box is installed in the hole and closed with a protective grill.

Hole in the finished foundation

Situations when the foundation design is flooded, not left in it, sometimes it is found. Therefore, you will have to make a considerable effort to make them.In principle, today, using modern technologies, it is not difficult to make several fictions in the finished foundation.

True, this is a costly matter, because you will have to use diamond drilling. This is expensive equipment that is not worth buying for drilling holes in concrete. It is better to invite a master who has it in stock. What needs to be taken into account:

  • All those positions regarding the location of the holes.
  • Accurately choose the diameter of the diamond crown in accordance with the diameter of the pride (by the way, it varies in the range of 100. 300 mm).

Many may confuse the drilling of the deceit in the foundation in relation to steel reinforcement, which is laid as a frame in a concrete base of the house. In this regard, you should not worry, because the diamond crown not only brings concrete well, but also easily copes with metal fillers. The hole will be even and smooth.

In a wooden basement

The base in wooden and frame houses is sometimes built from logs or timber. And if the basement has forgotten ventilation, then you will have to cut the holes in wooden elements. For this, it is best to use a chain saw (chainsaw).

  • Marking on the lower crown of a wooden structure.
  • A part of the crown is cut out exactly by marking.
  • A box of boards is installed in the resulting hole in the rectangular shape, which is precisely assembled in size of the cut outlet.
  • Often the ends of the fictions are simply broken through with boards. Both the first and second option is a simple cladding of cut ends to give them an attractive appearance. The assembled design does not carry any amplification, so for it you can use boards with a thickness of 20. 25 mm.

Ventilation of the foundation of a wooden house is more in demand, because wood begins to rot and collapse faster than bricks or blocks. Therefore, we must not forget to form it at the stage of building a building. And if, nevertheless, there were no fictions in the foundation of their own wooden house, then there is only one way out of the situation. to make them in the floor of the premises over the basement. Here, wondering how many fictions need to be made in the floor in order to provide the necessary air exchange in the basement, you will have to take into account the indicated norms and calculations above.

In this case, the holes are necessarily closed with grilles, it is better if put furniture on them on them, so that it is not visible. Let’s just say, the option is not accustomed. Smells from the basement will penetrate the house. Therefore, it will be correct if the outlets are made in office premises, and not in residential.

Correct location

How to do ventilation in the strip foundation?

Arrange a lot in the foundation base for fifteen to twenty centimeters below the upper edge of the tape. In the case of a low base, each outlet provides a pit.

The ventilation holes should be located evenly on all sides, opposite each other. Air streams. Placing in one blow, go through the opposite, taking away radon and moisture.

When forming the fictions, an interval of two to three meters is observed. If there are pieces inside, then for each compartment a minimum of one outlet is provided. FRIENSS arrange in the partitions so that the air flows form a draft.

In a word, it is recommended to adhere to certain rules:

  • From the corner section of the foundation to the extreme outlet should be no more than 0.9 m;
  • the number of arranged frauds is always even;
  • The choice of location above the surface of the Earth is always individual, but the recommended height is at least thirty centimeters to exclude the possibility of flooding the basement in the spring.

Organization in the construction of the foundation

Why are ventilation holes needed, we found out. Now let’s figure out how to make a lot in the foundation correctly.

It is best to do such work when installing formwork shields. To form a blow, you can use segments of the sewer pipe suitable in length. The algorithm of action looks as follows:

  • a formwork structure is formed, a reinforcing frame is installed;
  • On the walls of the formwork shields, place places under the installation of purges, taking into account the calculated data;
  • On each side of the formwork, openings of the through type are arranged, corresponding to the cross.section;
  • Prepared pipes are wrapped in roofing pieces and placed in holes, passing through through;
  • the free space between the pipe and the formwork wall is filled with sealant;
  • So that the blow does not deform from the weight of the concrete solution, it is recommended to arrange a small frame from reinforcing bars around it;
  • Having finished the fill, you should wait for the concrete to gain sufficient hardness. After about a week, a piece of the pipe, with the help of which it was formed, can be carefully pulled out.

How many fictions you need to do, we know, now we will consider how to arrange them in the foundation for a wooden house.

There are their own characteristics: the vents have between the first and second crowns or immediately over the foundation.

  • According to existing rules, the number of purges and points of their location are determined;
  • In the embedded log, holes are cut with a saw;
  • Each blow is strengthened by a frame of boards.

There are some rules on how to make perfumes in a finished foundation that is recommended to observe. The holes are formed during the construction of the foundation base, and the complexity of the process depends on the material from which the tape is built. Each option has nuances.


In most cases, the round shape is selected. If a plastic pipe is used, it should be filled with sand to avoid damage from the mass of flooded concrete.

In addition to workpieces from pipes, some developers form holes with the help of wooden chocks of the corresponding diameter. Do not do this, because after solidifying the solution, wooden elements are difficult to extract, the integrity of the base can be damaged.

Brick or block masonry

When arranging strangles with your own hands, choose rectangular or square dimensions for them. When organizing openings, use reinforcement to arrange frames. By the way, the rods located horizontally become an additional support for block material.

When driving brickwork, they get it, using halves of stone.

When can you do without fictions?

Sometimes you can do without fraud in a basement or foundation. For example, if:

  • The land under the house is covered with a film for vapor barrier. Then moisture will not penetrate the ground, but will linger under the film.
  • The basement has its own ventilation and good insulation.
  • The underput is associated with the first floor, which is well heated.
  • The walls of the foundation are protected by a concrete slab, and the soil is sand.

If there is only a foundation, but there is no basement, then he needs a lot only if it is absolutely not ventilated, and the soil is not covered with a special film or sand. In all other cases, outlets are still needed. Fiction in the foundation seem to be an optional detail on which you should not spend either strength or money. But in fact, the absence of fragrances will be much more noticeable than their presence. And if not immediately, then over time, moisture, which can even destroy the foundation of the whole house, ruin the underput and the basement, making it unsuitable for use by the mold of mold. And all this is easy to avoid, there is a lot of small fictions at the stage of building the foundation.

How many fingers do?

To calculate the optimal number of outlets, you need to familiarize yourself with the requirements of SNiP. They provide state standards. Typically, builders say that it is enough to make 4 holes with diamond drill on each side of the foundation. In fact, construction standards require a more thorough calculation for each individual object. The number of ventilation holes depends on the size of the foundation. the presence of internal jumpers and soil features on which the house is built.

The dimensions of the outlets

The formula according to the requirements, the SNiP is the ratio of 1 to 400 part of the size of the floor area. In practice, it turns out that for every 100 square meters of floor you need 0.25 square meters to allocate under the outlets. The diameter should be at least 0.05 square meter. This volume will provide an outlet of a rectangular shape of 20 centimeters for 22 centimeters. For round. you need a diameter of 25 centimeters. A practical way to make an outlet is to perform several holes with a small diameter instead of one large. The dimensions of small holes should be more than 11 centimeters.

The location of the fragrances on the body of the foundation

The outlets are located evenly throughout the foundation. They are raked off, starting from the corner and through the entire foundation. The distance from the corner to the first hole is not more than 1 meter, and the distance between the holes should not exceed 2.5-3 meters. If the foundation tape has partitions, then it is also necessary to make holes in them. Thus, it is possible to completely neutralize isolated air bags.

What to do if the fictions were not completed in the construction process?

During construction, it is not possible to take into account everything. Often when filling the foundation, they forget to lay the embedded for ventilation of the basement or their size are insufficient for normal ventilation. In this regard, increased humidity appears and the fungus begins to develop.

Drilling a monolithic foundation is a difficult task. Do this with a peorator and crown of a suitable size or a simple junk hammer. This method is not always realized, since often the thickness of the foundation reaches 50-60 cm, as well as due to the presence of reinforcement.

To solve this problem, there are installations of diamond drilling. The drilling of holes takes place quickly and without destructive vibrational impact, which occurs when using a peorator or chipping hammer.The technology allows you to perform holes of any diameter in concrete, reinforced concrete, brick foundations.

Our company specializes in the provision of diamond drill services and diamond cutting. You can order drilling holes in the foundation of your home by calling: 7 (499) 677 67 40.

for diamond drilling outlets (fictions) in the foundation.

Minimum order. 6000

The price includes drilling 3 holes, each of the following is calculated according to the table. The cost can also be changed depending on the location of the object and drilling conditions.

When ordering from 10,000. all holes are calculated according to the table.

The price is valid with a diameter of holes of 100mm. 120mm.

  • remoteness of the object;
  • work in underground space 1m-1 high.5m. coeff 1.2
  • Work in underground space 0.5M-1m-coeff 1.5

What is necessary to perform work on drilling of fictions (outlets) in the foundation:

  • Marking (if necessary, experts will prompt the necessary arrangement of holes in place);
  • Electricity 220V is at least 3 kW;
  • Water source (water supply, well, container with water at the rate of 10-15 liters of water per hole);
  • Access to the foundation (from the foundation, it is necessary to remove siding, foam or other variants of the skin in places of drilling outlets)

If you still have questions or you need holes of another diameter Call Tel: 7 (499) 677 67 40

Photos from objects for drilling ventilation holes in the foundation

Cities of the Kaluga and Tula region, where our company carried out work on drilling fictions (outlets) in the foundation.

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Indicate your contact details and order information. After receiving, we will call you back in the shortest possible time.

What size should there be holes

FRODUCES IT IS ARE NOT MOTED OF THE PROPRODY. There are certain standard ones that regulate their number, as well as the way of location in the foundation. SNiP with serial number 31/01/2003 is taken as the basis. In one of its points (9.10) indicate the area of ​​the fictions that should be present for ventilation of the basement. The total area of ​​all the fictions should be more than four hundred part of the underground area. That is, first it is necessary to calculate the total area of ​​the underground. If it is correct, then it is enough to multiply the width by the length. For a complex form, you need to divide the underput into simple figures and summarize their area. At the same time, the area of ​​the foundation is not taken into account.

If the internal area of ​​all rooms is 120 m2, then the total area of ​​the fictions will be 0.3 m2. If you translate these values ​​into more visual ones, then round vents should be with a diameter of at least 25 cm. For rectangular fuses, the dimensions in minimal values ​​should be 10 × 50 or 20 × 25 cm. With a large area, the sizes of the fictions can turn out to be significant. For a private one.story house, this can be a problem. To solve it, you can make a smaller breath, but increase their number around the perimeter of the foundation.

The location of the fictions in the foundation tape also has some nuances. The holes cannot be located on the upper edge. The upper point of the lot should be at least 15 cm below the upper edge of the foundation tape. There are times when the foundation does not rise above the surface of the soil to the required level, then you need to dig a small pit and enclose it so that the earth does not pour out into the underput. The location of the periods should not be chaotic. They should be evenly distributed on each side of the foundation. Those perfumes that are on the opposite sides should be opposite each other so that the air masses circulate freely.

If the foundation provides jumpers for rheat, then holes must also be made in them so that the air circulates. The minimum distance that should be between the poor are 2 meters. There should be a minimum of one time for the partition in the foundation. In addition, if it is one, then the size of such a deeper should be several times more than the one that is located in the outer wall of the foundation. Instead of one large, you can provide several with a smaller diameter. The subfosure is an excellent place that animals and insects are happy. To prevent this from happening, the holes must be closed with a metal or plastic grill, which will serve as a barrier to penetrate.

Questions and answers

Question: Why it is necessary to insulate the foundation if the ventilation of the strip foundation still in the winter will reduce these efforts to the zero result?

Answer: If the base of the house and soil are insulated, then in the winter the temperature in the underground will be higher than the dew point and condensation will not form. With an insulated base, you can close the perfume with plugs, opening only sometimes two, on the opposite sides of the basement. Thus, the cold will not lower the floor temperature in the house, and the humidity level will be within normal limits.

Question: How to make a basement ventilation in a wooden house?

Answer: I ventilation of the basement in a wooden house is no different from the ventilation of the base of the brick, railway or aerated concrete house. The requirements are some, the main thing is that all the premises of the basement have holes for free circulation of air masses.

Question: In all recommendations for the arrangement of the foundation ventilation, dimensions are given at the rate of rectangular cross.section of the purge. How to translate the received data into an equivalent diameter?

Answer: You can use the tables given in a specialized literature, or calculate yourself by the formula:

where: de is the equivalent diameter in mm; a and b. sides of the rectangular hole.

We hope that our publication will help you equip the foundation of your home with a high.quality and effective natural ventilation system, thanks to which the construction will serve you for many years.