Inspection pit ventilation in a garage: specifics of arranging an air exchange system

In household and household buildings, as in the house, a microclimatic balance is required. One of its components is a high-quality ventilation system. In addition to the vehicle’s containment area, ventilation of the inspection hole in the garage is necessary, as and she participates in the general air exchange of the garage.

We will talk about how to organize a stable change in air mass in a box buried in the ground. We will show you what kind of system it is desirable to prefer, explain the reasons. Our recommendations will be useful to independent home craftsmen who want to keep both construction and equipment in order.

Benefits of a viewing pit with ventilation

Despite the small dimensions of the inspection compartment, its constant drying and ventilation is very important. Moisture from the car often gets into it, therefore, condensate accumulates, destroying the walls. Because of this, the pit gradually comes into a condition not suitable for repair work.

Proper organization of ventilation will give a positive result:

1. It will bring the temperature background back to normal.
2. Normalizes the humidity indicator, which will have a good effect on the condition of the car, tools, metal surfaces of the garage. In addition, dampness can create the prerequisites for short-circuit wiring of the pit lighting line.
3. It will exclude conditions favorable for the appearance of a fungus that is able to destroy even concrete and brick elements of both the room as a whole and the viewing hole in particular.
4. Prevents the accumulation of harmful fumes of fuel, paint and varnish materials, engine oil, technical fluids. This is important because reaching a certain concentration, they can cause fire and poisoning.

From a hole in which ventilation is not provided, air saturated with moisture and various vapors will enter the room. This will negatively affect the health of the motorist.

The lack of air flow in the inspection compartment will lead to the fact that the car body in 2-3 years will have to be overhauled

Since the motorist sometimes spends a lot of time in the inspection department, the air in it should be regularly updated.

Types of ventilation for a viewing hole

When the ventilation device in the inspection pit, as in other cases, proceed from the laws of aerodynamics. Therefore, there are three options - natural, forced ventilation, as well as combined. The first method, due to the successful coincidence of price and quality, is preferred by many motorists.

Air masses circulate due to the difference in pressure of air flows with different temperatures. In this case, fresh jets of air squeeze out the exhaust warm air. The circulation becomes more intense if the pressure drop, and therefore the draft increases.

During the warm season, ventilation with natural motivation does not work well. This is explained by a slight discrepancy between the temperatures of the air from the outside and inside. This circumstance makes us think about a forced ventilation device, although such a small compartment of natural ventilation is often enough to dry.

SNiP under number 21-01-99 stipulates that every hour the air masses in the room should be updated. When the vehicle is brought into working condition, the indicator increases 4 times

Considering that for the garage the requirements for air exchange are increased, it should be possible to increase the amount of supply air. Maximum efficiency can be achieved using a forced two-channel ventilation system.

In this way, both the optimal influx of fresh air masses through mechanical devices and the timely removal of contaminated materials will be ensured.

Organization of ventilation of a viewing hole

The ventilation system of the aboveground part of the garage is extremely simple, and the hood in the inspection pit of the garage is more difficult to arrange, since it has its own characteristics.

You can implement it in two ways:

1. By ventilation device, which is part of the ventilation system of the entire building.
2. Separate inspection bay system, separate from general ventilation.
   The most effective solution - standalone forced-air and exhaust ventilation system as an addition to the air exchange of the main building.

Before starting to equip the ventilation in the inspection pit, you should develop a general scheme for the entire garage building. It marks the holes in the wall, foundation, base for the subsequent placement of air ducts.

For ventilation to work effectively, it is necessary to observe the ratio of the diameters of the exhaust pipe and the supply. The first should be equal to the second or slightly less, but not more

The project takes into account such moments as the volume of the room, the number of cars, the underground or elevated version of the pipe placement. They are also considering the optimal route for the movement of air masses.

If the groundwater is not deep enough, in addition to the ventilation system, it is necessary to provide for a good waterproofing of the inspection hole. Then dampness will not accumulate through the floor and walls, and ventilation will better cope with its task.

For waterproofing along the walls of the pit, dig trenches. A waterproofing layer of durable polyethylene is laid from the bottom. Next, the soil is returned back and compacted

Guided by building codes, it should be noted that with natural air exchange for each square meter of the garage room there should be about 1.5 cm of the duct diameter. So, if you take a garage room with an area of ​​10 m², then for the installation of the ventilation system, pipes with a diameter of 15 cm are required.

In the case when the area of ​​the room is 2 times larger, then the diameter of the pipe increases 2 times. If there are several holes, the calculated diameter is divided by their number.

There is another formula for determining the parameters of ventilation openings. Their total size should correspond to 0.3% of the area of ​​the room. This method is usually used in the calculation of a mechanical single-channel system.

Natural-type ventilation installation technology

In the process of finding a solution to the problem, how to make a hood of this type in the inspection pit and in the garage should be guided by the following principles:

1. At the edges of the pit, it is necessary to leave a gap of about 150 mm wide.
2. Boards for sheltering the pit must be placed with a 100 mm gap.
3. In the side opposite from the hood, a clearance is necessary.

In this case, two boards are removed from the plank for air flow. To create conditions for the hood, one board is removed. In the opposite corners of the inspection department place the supply and exhaust ventilation ducts. The end of the inflow pipe is left at an average distance of 25 cm from the floor.

If the hood is already present in the garage, you can solve the issue of ventilation of the inspection hole by laying existing ducts in it

At the next stage, stepping back from the surface of the earth about 10 cm, place the top of the supply pipe. The exhaust duct is located as close as possible to the cover of the inspection hole. The opposite end of the exhaust pipe extending outward is elevated above the highest point of the garage roof by at least 0.5 m. When installing, the horizontal position of the pipes is monitored.

In winter, the air inlet must be regularly freed from snow. It is easier to increase the height of the hood, and at the same time increase traction. To improve circulation, the pipes are equipped with deflectors. The supply air duct is equipped with a grill to prevent insects and rodents from entering it.

In cold winters, pipes must be insulated, otherwise they may freeze. In an unheated garage, natural ventilation can function poorly not only in summer but also in winter.

In the room, often plugs are installed on the pipes, allowing, if necessary, to completely shut off the circulation or limit its intensity

When the car’s engine is running, it becomes a source of heat, but two hours after turning off the temperature in the room does not differ much from the street temperature. The effectiveness of natural ventilation is falling.

The solution is simple: to maintain air exchange and prevent freezing of condensate in the exhaust duct, an ordinary 40-watt incandescent lamp is used. The cartridge is suspended under the opening of the channel and include. The lamp generates heat, which is sufficient for air to move at a speed of 0.2 to 0.4 m / s.

It is important to insulate the channel and prevent moisture from entering it. It should be noted that the incandescent lamp gives little heat, and it is unlikely to be enough for the entire length of the ventilation duct.

Replace the incandescent lamp with an LED or fluorescent analogue is not worth it. They generate much less thermal energy. It is better to use a low-power infrared device.

Forced ventilation system

A forced-ventilation system in the inspection pit is not installed very often. In this case, mechanized means of motivation are used. Sometimes they also provide for air heating through a duct heater.

The supply of air masses is carried out using duct fan. Monoblock air-handling units in this case are not used rationally. And the fan for inflow is not always used, only if there is such a need.

Since the air removed from the inspection pit is filled with moisture, it must not be allowed that it directly enters the underbody from the exhaust opening. This will lead to rapid corrosion of the structure.

To implement a forced ventilation circuit, electrical power is required.Additionally, the system is sometimes equipped with timers so that it turns on and off automatically. In some cases, the ventilation control is connected to a light switch.

Compared to natural ventilation, a forced system has many advantages:

1. The possibility of increasing efficiency, as a result of which an increased volume of fresh street air quickly displaces the waste mass with an admixture of harmful substances.
2. Exclusion of the dependence of the air supply on external factors due to the presence of fans in the system. Air masses can be fed into the desired zone, in a certain volume, at the right speed.
3. The car will always be in favorable temperature conditions.

If there is no good reason, it is impractical to equip the inspection compartment with mechanical ventilation. This option is better for a cellar.

Combined pit ventilation system

The combined type system is the most popular. It provides for the presence of mechanics in the hood of a garage or pit, as well as the flow of air, carried out according to a natural scheme.

A fairly quick flow of fresh air into the garage is possible due to the presence of a rarefied pressure zone. It is created by the fan during the extraction of dirty air. At the same time, it is necessary to preserve the possibilities of natural ventilation in case the electricity is cut off and the fan will not function.

When organizing a ventilation system in a garage with a viewing hole and a cellar, the preferred direction of the wind must be taken into account. It is desirable that the supply pipe is on the windward side, and the exhaust pipe is on the leeward side

For safety reasons, two parallel lines are laid or a hole in the installation site of the fan is made slightly larger in diameter. The advantages of the combined system are that it is independent of the outside temperature. This method of normalizing air exchange is quite cheap.

As a minus, it can be noted that the air ducts are quickly polluted, so they must be cleaned periodically. In addition, the air flow is not heated.

Conclusions and useful video on the topic

Video clip on how to equip the hood in the garage and in the inspection pit in particular:

The experience of creating ventilation in the garage and basement with your own hands:

To obtain the expected effect, ventilation in the inspection compartment of the garage must meet the installation rules and the feasibility from an economic point of view. The choice of system should be made based on the specifics of the building, size. Only using these factors, it will be possible not only to create optimal conditions for car maintenance, but also to spend money rationally.

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