Basement floor ventilation: general arrangement technology + methods of effective air exchange

Properly equipped ventilation of the basement floor, during the operation of the latter, relieves people from contact with dampness, mold, and a number of other pathogenic organisms and gases.Therefore, the presence of a hood can be ignored only in exceptional cases.

It is important to understand that creating such a system requires certain knowledge and skills, even if specialists are involved in the work.

Let's look together at the methods of ventilation and the intricacies of its arrangement.

Popular ventilation methods

Relevant guidance documents and practice show that basement floors can be effectively ventilated in several ways: naturally and forcefully.

In addition, today a mixed or complex method of arranging an exhaust system is increasingly being used - which has the characteristic features of both of the above options.

And also when implementing mixed ventilation, additional equipment is used.

Modern technologies have made breakthroughs in various fields. But this did not particularly affect the ventilation system of the basement, therefore, like a century ago, you will have to make vents, forming them with wooden planks of the appropriate size. And in difficult cases, when the desired result cannot be achieved, it is necessary to create air ducts and ventilation pipes

Based on the listed methods, all ventilation schemes in demand today have been created, so you should familiarize yourself with each of them. But first, let’s look at the general technology for arranging basement ventilation.

Technology for creating a ventilation system

Although there are several varieties of plinth ventilation systems, there is no variety of schemes and technologies. The basis of any hood is natural supply and exhaust air exchange.

The layout of any method is similar. That is, it all starts with planning and placement of products, ventilation pipes.

If the room area is large (over 50 m²), then a fan of sufficient power should be added to the design. In this case, the inlet openings must provide a supply of clean air.

If there are several rooms and it is necessary to maintain a separate microclimate in each of them, then you will need to create complex ventilation systems.

Which involve the use of natural or forced exhaust in individual rooms, and a large amount of additional equipment can be used for its implementation.

To replace contaminated air masses, special ventilation openings are used, which are usually distributed on all sides of the building. Which in itself makes the method more effective

The most important point is the number of ventilation holes. If they are missing, the system will not be able to cope with the task even in a small basement room.

Since numerous stagnant zones with high humidity and other negative phenomena will form.

This indicates that there should be a lot of air ducts, and their exact parameters are indicated by the profile Code of Rules - SP 54.13330.2011. Where it is clearly noted that the total area of ​​the ventilation openings should be 1/400 of the entire area of ​​the basement floor.

Despite the characteristics of each type of basement ventilation system, the most important issue is still the correct use of exhaust pipes and openings. So, in the latter case, the air ducts should be located at least 1.5-2 m from each other, otherwise it will be difficult to achieve the expected result even when using modern equipment

The same document states that these elements should be located evenly around the entire perimeter. Another rule contained in the joint venture is to indicate the exact area of ​​​​each duct, which should not be less than 0.05 m².

The most important and most commonly used element in any basement ventilation scheme is the exhaust vent, called the vent. For maximum efficiency there should be a lot of them, and around the entire perimeter of the building. It is also important to understand that these structures are divided into supply and exhaust. And they must be placed on opposite walls, opposite each other

And then to determine the parameters and draw up a ventilation scheme, all that remains is to perform a simple calculation.

Why do you need:

1. Divide the area of ​​the basement by 400. The result is the total area of ​​the holes in the basement;
2. The resulting value should be divided by 2 (pairs of supply and exhaust structures) and placed evenly along the entire perimeter of the building.

It should be remembered that, according to the joint venture, you should not make a round hole with a diameter smaller than 25 cm, and the minimum size of rectangular ones should be 20x22 cm.

An exception may be situations when several smaller air ducts are placed nearby - if round air ducts are made, their diameter may be not 25 cm, but 11 cm.

You should not make the ventilation holes as large and rare as possible. For example, in a house whose ground floor area is 100 m² with a required ventilation volume of 250 cm², they should not be divided between 4 large ones, as many developers do, but divided into 10 small ones.

The scheme in which air exchange is ensured using inlet and outlet openings is considered classic or typical. Since it is suitable in most cases, without any changes

It’s even more practical to make two dozen minimum permissible holes, for example, round ones with a diameter of 11 cm and place them approximately every one and a half meters around the entire perimeter. And such a ventilation scheme for any basement floor will be as efficient and profitable as possible.

If the vents do not cope with the function of replacing air in the basement room, then air ducts are added to the ventilation system - pipes, which are additionally equipped with fans and other additional equipment characteristic of a forced-air system.

Features of natural air exchange

As the name indicates, this ventilation method is based on the laws of physics, so the use of any special equipment is not expected.

Air exchange occurs due to the temperature difference inside the basement and outside, as well as the pressure drop that follows this phenomenon.

The order of organization of the system

To ensure effective air exchange, a number of operations should be performed, in the following order:

1. Calculate the area of ​​air ducts. It is optimal to carry out this procedure at the design stage of the entire building. If mistakes are made, then adjustments can be made even after the facility is put into operation.
2. Calculate the number of exhaust openings and determine their location. This is also done at the design stage.
3. Form vents. Since the efficiency of the entire system, as well as the aesthetic properties of the base, depend on this operation, this issue will be considered separately.
4. Install into the holes provided deflectors or just close them protective grilles. Which prevent animals and objects from getting inside the premises.
5. Test the formed system. What can you do with a burning candle?

In addition, if necessary, you can perform work on decorating the resulting air ducts.

Since natural ventilation works based on temperature differences leading to pressure differences, the inlet opening should be placed just a couple of tens of centimeters from the floor. And the exhaust analogue is as high as possible, possibly even in the ceiling

If the performance of the ventilation holes (vents) is not enough, then the following should be done:

1. Use exhaust pipes for air exchange.
2. Install the supply pipe at a level of 20-40 cm from the ground floor floor level.
3. Place the exhaust pipe opposite the supply pipe, that is, in the opposite wall of the room.

The ventilation hole of the exhaust pipe should be located as close to the ceiling as possible, and if possible, directly into it. And it should come out above the roof, about 0.6 m above the roof.

Regardless of which method of placing air ducts is chosen, it should be remembered that there should be no unventilated corners. To avoid such a defect, the nearest ventilation hole should be located no further than a meter from the specified location.

But experts often recommend using the standard that is used in many European countries and placing the first vent no further from the corner than 90 cm, which is more likely to prevent negative processes from occurring on the ground floor.

How to shape holes?

There are no requirements for the configuration of the holes, that is, they can be made of any shape, even triangular, which is now becoming fashionable.

But the most popular are:

• square;
• rectangular.

They are easy to form. To perform such an operation, it is enough to use 4 planks of the required size, from which a geometric figure of the desired shape is simply built and installed in the right place, after which it is laid out with mortar or brick.

Holes of other shapes are made in a similar way, for example, triangular ones, which are increasingly popular today.

The ventilation holes can be of any shape. The most popular ones today are rectangular, square and round vents. They are easy to shape and look aesthetically pleasing

But more and more often you can find their round analogues, which are easily created using a plastic tube of the required diameter (often 110 mm) and length, which should be equal to the thickness of the base or foundation.

It is simply placed in the desired place and covered with solution. The result is perfectly straight holes.

If ventilation ducts were not made when creating the basement floor, then they are created using diamond drilling. As a result, they also turn out to be round in shape.

Important system features

The number of exhaust openings plays an important role, but when creating them, you should always remember that their location is an equally important feature that significantly affects the efficiency of the entire ventilation system.

Thus, pairs of inlet and outlet ducts should be placed strictly opposite each other.

The main elements of the basement ventilation system, which are vents, should be placed around the perimeter of the building as often as possible. And not symmetrically, but precisely in those places. where air exchange is especially necessary to remove moisture and gases, which may include radioactive radon

You also need to know that:

1. Exhaust openings should be located at least 40-60 cm from the ground surface. This will reduce the likelihood of them being clogged with snow, which should not be allowed, since the efficiency of removing contaminated air masses will decrease or the process will stop altogether.
2. Since natural ventilation operates on the principle of temperature and pressure differences, the exhaust pipe from the base can be taken to the street by extending the main line through all floors. Which will make the system more expensive, but also as efficient as possible. It is placed 30-60 cm from the roof, as this will eliminate the possibility of snow getting into the air duct.

All input/output channels must be protected by grilles that will prevent rodents, pets, birds, and insects from getting inside.

If a similar temperature has established on the ground floor and the functioning of natural exhaust has stopped, then a heater or any other heating device should be installed in the room. This will help create the necessary conditions for the resumption of air exchange as quickly as possible.

Exhaust pipes can provide effective air exchange on the ground floor. But you should remember that this is a more expensive option for creating air exchange.

Natural exhaust exhibits its best properties when maintaining a microclimate in small rooms.Therefore, if the area of ​​the basement floor exceeds 50 m², then you should not take risks and use a forced air exchange system or a mixed option.

Otherwise, the maximum effect may not be achieved, which will lead to negative processes.

Subtleties of the forced exhaust device

This type of ventilation system is structurally similar to the natural one described above. But what makes them different is the presence of fans and other additional equipment, which increases, and radically, the efficiency of exhaust hood in basement rooms.

Forced ventilation is considered a costly method of eliminating contaminated air masses.

And yet, such a disadvantage is offset by the lack of dependence on natural conditions, the complex configuration of the basement floor, and mistakes made when creating natural hood. That is, from everything that makes the system ineffective.

The simplest forced exhaust system is quite easy to set up - just install it in the exhaust air duct duct fan.

The forced exhaust system is similar to the natural one (described above), the only difference being the presence of fans. Which are mounted in air ducts in the manner shown in the picture

If the basement floor is divided into several rooms, and everything needs to be forcedly ventilated, then there will be little exhaust equipment in one room.

As a result, you will have to get out of the situation in the following ways:

• creation of air channels laid under the ceiling in all necessary rooms, which are formed from metal or plastic pipes;
• installation of exhaust and supply fans.

Supply fans will help solve the problem in particularly difficult conditions. Usually they are used exclusively in conjunction with exhaust hoods.

Forced ventilation of the desired basement floor is carried out if natural exhaust capabilities are insufficient. For example, this happens when the floor area is too large, there is significant humidity or gas formation. But the only important difference between this air exchange technology and the natural one is the presence of a duct fan, which significantly increases efficiency

Since the fan is the basis for high-quality ventilation of any forced-air system, you should familiarize yourself with the technology for its selection. Since not every product will cope with the task, and many will even pose a danger to the life and health of users.

Necessary equipment to assemble the system

The following can be used to provide forced exhaust:

• fans;
• Humidity sensors, their more outdated analogues, which are hygrometers.
• thermostats;
• heaters.

Most often, fans are used to obtain the desired result. The most important characteristic of such equipment is performance and it will have to be calculated in each specific case.

But this is not difficult to do, since all you need is to use a special formula for calculation. According to which, the optimal fan power will be the derivative of the building volume of the required room and the multiplicity of the amount of air volume exchange for each hour.

Fan performance for forced system
ventilation is the most important performance characteristic on which efficiency depends. And if it is not enough, then forced air exchange is similar to ordinary natural one. In addition, such a product must be safe, and if the base is habitable, then silent

In addition, important performance characteristics of any exhaust fan are: safety, noiselessness, functionality. It is advisable to use a waterproof device.

Humidity sensors allow you to generate a signal to turn on/off the equipment in use. For example, the same fans. This will allow you to eliminate dampness, without overpaying for electricity. After all, ventilation devices will work in situations where this is necessary.

Thermostats are designed to keep the temperature in the basement stable. They are used to provide a command signal to turn on/off the air heater and other equipment used to heat the supply air.

This allows not only to maintain a given temperature, but also to create a pressure difference to ensure the required performance of a ventilation system without fans.

Stages of installation of a forced system

The installation of a forced ventilation system is carried out in several stages.

Which include:

1. Calculation of the area of ​​vents and their quantity. These operations are similar to those performed when designing a natural hood (listed above).
2. Fan performance calculation.
3. Creation of air ducts in compliance with the requirements specified for natural exhaust.
4. Installation of fans and additional equipment if necessary.
5. Functionality check.

All calculations are made at the design stage of the basement floor.

When arranging ventilation for the basement, it should be remembered that the main goal of such a procedure is to create effective air exchange, without stagnant zones.Therefore, it is necessary to comply with the norms of the profile joint venture, which state that the area of ​​the exhaust openings should not be less than 1/400 of the area of ​​the floor itself. The only exceptions are situations with increased background radiation.

Mixed and complex ventilation systems

Mixed systems are among the most productive, as they take into account the specific conditions in each specific situation. They are based on the conventional natural exhaust scheme described above, with modern additional equipment adding efficiency.

Any scheme of a mixed or complex ventilation system implies the presence of a large number of structural elements and equipment.

In this case, standard solutions are not the way out. Since it is necessary to perform large volumes of calculations in each specific case.

Mixed and complex air exchange options are the most effective and at the same time expensive. Since it is assumed that a large amount of additional equipment will be used. Among which are complex air ducts, which should be used only in extreme cases, and laid only during renovation of the basement floor

Such systems are useful when the ventilation system needs to create different conditions in individual rooms of the basement.

For example, if a pantry, gym and wine cellar are located underground. Then, in the place where something is stored, you can take advantage of natural ventilation; for effective air exchange in the training room, an exhaust fan should be installed instead of a vent.

And where wine is stored, which requires a special regime, in addition to all of the above, it is necessary to use a number of additional equipment.Which will help maintain the microclimate stable.

In a room with wine racks you will need check valves, which exclude the entry of external air into the room, air conditioners, control systems, etc.

The exact layout of mixed or complex systems is created in each individual case, taking into account the needs. When arranging, you should use the same technologies and schemes as when creating other types of hoods.

If you didn’t take care of the ventilation of the base at the stage of creating the design of the entire building or simply made a mistake, then everything can be corrected with the help of diamond drilling, which will provide the ventilation with a perfectly even shape

For example, if the basement floor is divided into several rooms, then you should remember that adjacent walls are an obstacle to the movement of air masses. As a result, the creation of vents, air ducts, and channels is required.

There are several more articles on our website where we talked in detail about the arrangement of ventilation in various rooms. Recommended reading:

1. Ventilation in the garage.
2. Organization of cellar ventilation.
3. Arrangement of ventilation for the steam room.
4. Pool ventilation.
5. Installation of a basement ventilation system.

Conclusions and useful video on the topic

The video will allow you to deepen your knowledge of arranging basement ventilation and creating holes with diamond cutting, which will help you avoid mistakes that lead to financial losses.

An example of working ventilation in the basement of a private house:

Although there are several types of hoods, the basis for ventilating basement spaces is the natural way. Which ensures efficient exchange of air masses for a plinth with an area of ​​up to 50 m².

If the dimensions of the basement floor are larger than the specified value or the area is divided into several rooms, then the effectiveness of natural exhaust will not be enough.

In such situations, modern equipment will be needed to organize a forced ventilation system with the arrangement of ventilation ducts equipped with fans to speed up the process of supplying fresh air to replace the remote air for each of the rooms on the ground floor.

Do you have personal experience in installing a basement floor ventilation system? You can share your own experience or ask questions about the topic of the article in the block below.