Ventilation cleaning: cleaning the ventilation ducts in an apartment building

Alexey Dedyulin
Checked by a specialist: Alexey Dedyulin
Author: Lyubamira Lysyuk
Last update: March 2019

Many residents of multi-storey buildings, especially old buildings, can tell about what culinary preferences their neighbors have, what they indulged in for dinner and what served for lunch. However, we are not talking about telepathy, the neighbor's menu can be recognized simply by the smell that is felt in the apartment.

If this happens all the time, it means that ventilation needs cleaning, which has ceased to cope with the functions assigned to it. Our recommendations will help restore normal air exchange in the apartment. Minor blockages can be eliminated independently, and to solve more complex problems will have to call specialists.

We will tell you how the ventilation system of the house is arranged, what are the causes and signs of a malfunction of its operation. Here you will learn how to set up exhaust air and supply fresh air. For visual perception, photo collections, diagrams, videos are attached to the article.

Functional purpose of ventilation

The air we breathe in the apartment only seems clean. In fact, it absorbs all the smells coming from the kitchen, carbon monoxide from the stove. Particles of dust, villi from clothes, carpets, and pet hair fall into it.

Harmful microorganisms and bacteria accumulate in the air, which contribute to the development of serious diseases, moisture and steam coming from the bathroom, cause the formation of fungus and captivity. All this negatively affects the microclimate of the room, contributes to the appearance of lung diseases, allergies and other ailments.

Ventilation, which performs several important functions, helps to avoid negative consequences for health:

  • provides clean air to the apartment,
  • allows you to remove odors, dust, bacteria, carbon monoxide and other harmful components from the room;
  • regulates humidity level.

Ventilation is one of the vital engineering communications of an apartment building. The State Commission will never accept an object in which the ventilation system is absent or faulty.

Mold in the apartment
If there is insufficient airflow and poor ventilation, mold and fungus may form on the walls of the room

The device of a common ventilation system

House ventilation is a complex engineering system, its arrangement depends on a number of factors, among which the most important is the total number of storeys of the building.

The installation of ventilation shafts in multi-storey buildings is made according to different schemes, eg:

  1. Each apartment has its own exhaust duct with access to the roof.
  2. Exhaust ducts coming from the apartments are connected into one horizontal duct, which collects all the incoming air, and then through the common channel leads to the roof.
  3. Exhaust satellite channels leave each apartment in a common shaft leading to a warm attic, which is used as an intermediate chamber. In the attic there is one large extractor hood to remove all the air to the roof.

The ventilation performed according to the first scheme is effective for low buildings. It was very common in earlier times, when mostly houses were built not higher than four floors. The arrangement of such a system requires a lot of space, and it is not practical to use it for high houses, so today it is practically not used.

The second scheme was used everywhere in Khrushchev and in houses of 9-16-storey buildings. In new buildings, the latter scheme is most often used, which is considered the most effective ventilation system for buildings with large floors.

Ventilation schemes in an apartment building
The figure shows the four schemes used to equip the exhaust system in multi-apartment buildings. The first is used in 3-4 storey buildings, the second and third are used in 5-9 buildings, the fourth scheme is used in modern high-rise buildings (+)

Natural air exchange in the apartment

There are a number of requirements that ventilation in residential premises must meet.

In accordance with GOST 30494-2011 it must provide:

  • air quality indoors not lower than the permissible limits (up to 1000 СО2 cm3 / m3);
  • optimum humidity premises within 30-60%;
  • air velocity no more than 0.2 m / s.

Apartment buildings use natural ventilation. In each apartment (in the bathroom, toilet, kitchen, pantry) there are exhaust ducts through which the dirty waste air leaves the room. Streams of clean air enter the apartment through the windows, cracks in the windows and doors.

Natural air circulation
To allow air to circulate freely throughout the apartment, small gaps of 1-2 cm are left between the floor and the interior doors

Such a ventilation scheme was previously used everywhere in the construction of five and nine-story houses. In the old days, wooden windows were installed in the houses, which, due to the large number of slots, did their job well.

However, in new homes, this scheme works inefficiently, since metal-plastic window structures are tight and do not allow air to pass through. In modern buildings, forced ventilation systems and a variety of supply and exhaust devicesthat ensure optimal operation of the house ventilation.

Supply unit above the window
The supply air ventilation unit can be located directly above the double-glazed window, as in the figure, or on the wall in the immediate vicinity of the window

Reasons for inefficient hood operation

The problems in the operation of the exhaust system are familiar to the owners of apartments built in the Soviet era. Residents of new buildings for the most part are deprived of the pleasure of attending the meal of their neighbors, as new houses are equipped with modern forced ventilation complexes.

Such systems do not allow odors into the apartment.

Dirty exhaust duct
The cobweb, dirt and dust accumulated in the exhaust duct are one of the main causes of insufficient air circulation in the room

Reason # 1.The decrease in ventilation efficiency in old houses, in principle, is a fairly predictable process. The main reason is the banal clogging of the ventilation duct, which over time accumulates garbage, dirt, dust and other waste coming from the room.

As a result, the outlet narrows and becomes unable to fully process the dirty air that is taken.

In apartment buildings, united by a common ventilation shaft, pollution from individual channels enter the common house system. Gradually, the mine becomes clogged with debris and can become completely clogged. A process that lasts for years can cause the functioning of the ventilation system to be paralyzed.

This problem can be solved by duct restoration and eliminate the root causes of their partial or complete blockage.

Reason number 2. Another premise contributing to the deterioration of air exchange is the presence in the neighboring apartment of a powerful kitchen hood. However, this is understandable. Household natural ventilation is designed for air flow up to 90 m3/hour.

A single hood creates an airflow of more than 1000 m3/ hour, of course, neighboring ventilation ducts that go into a common shaft suffer from this. And if the hood is not one, but every second neighbor? The answer is obvious.

Extractor fan in the kitchen
Hoods significantly improve the microclimate in the neighboring kitchen, but it can also negatively affect the operation of natural ventilation in other apartments connected by a common house ventilation shaft.

Reason number 3. The replacement of wooden windows with metal-plastic ones is also a factor negatively affecting the operability of the ventilation system. It turns out that the leakproofness inherent in modern double-glazed windows is not always playing into the hands of residents of old houses.

In Soviet times, only the lazy did not scold builders who made mistakes in installing windows and doors. As it turned out today, the "culprits" worked strictly according to the instructions for the benefit of residents, becausefor the full functioning of natural ventilation requires gaps, which were in abundance in old wooden windows.

The holes provide a constant flow of fresh air from the street, and hermetic metal-plastic constructions overlap it on the contrary. As a result, the humidity in the room rises, the windows fog up, mold and fungus form on the walls.

Fogged windows
Modern double-glazed windows cannot provide full air exchange in an apartment of a multi-storey building, which uses a natural ventilation system. Misty windows indicate excessive humidity in the room and the need for forced ventilation devices

Reason No. 4. To a large extent, the operation of the ventilation system depends on the season. Most often, problems with the hood appear during the hot period, while in winter the hood works properly.

The fact is that the efficiency of the system with natural ventilation is directly dependent on the temperature difference inside and outside the building.

In summer, the temperature in the street and in the apartment is almost the same, therefore, problems appear. According to old SNiPs, it was assumed that in hot weather air exchange will be carried out by ventilating the room with open windows.

Signs of an urgent need for cleaning

The reasons for the poor ventilation listed above indicate one thing - the system needs constant monitoring and periodic cleaning.

You can understand that the ventilation duct needs to be cleaned by the following signs:

  • dust, cobwebs formed near the exhaust vent, debris accumulated;
  • the ventilation grill is covered with black coating, soot and grease;
  • in the summer, the apartment began to heat up very quickly;
  • after wet cleaning, after a short period of time, dust appears again;
  • the drafts that occur in the apartment when the front door is opened are much weaker than before.

To finally make sure that the ventilation needs to be cleaned, you can additionally check each vent. To do this is quite simple with the help of improvised tools. When checking traction, it is necessary that at least one of the window leaves in the apartment is open.

Dirty ventilation grill
Such a grill clearly indicates that the ventilation in the apartment is practically not working, and the exhaust outlet requires urgent cleaning

Home methods for checking the performance of ventilation ducts:

  1. Bring a burning candle, lighter, or lit match to the ventilation grill. If there is good draft in the duct, the flame will be directed towards the hood. Fire burning evenly indicates a lack of ventilation.
  2. Take a piece of paper or a piece of newspaper and attach it to the hole. During normal operation of the ventilation system, the paper attracts to the grate, and it does not fall.

If it turns out that the ventilation does not work at all or works extremely poorly, you need to clean it. Cleaning of ventilation ducts in an apartment building is carried out by specialized services. In their arsenal there is inspection and cleaning equipment ventilation ducts.

But if the need arose, each tenant of the house can clean their own duct section independently.

Open flame traction test
When checking the draft with an open flame, one must be extremely careful not to accidentally set fire to the cobwebs and accumulated debris inside the vent. This is especially true for residents of gasified houses, where a fire may occur due to a gas leak in one of the apartments of the entrance

Ventilation inspection by licensed services

The ventilation system is a common property, the management company is responsible for its maintenance and safe operation. In Government Decision No. 410, rules were developed that should guide the Criminal Code in inspecting and cleaning house ventilation ducts.

According to the Rules, the inspection of chimneys and ventilation, as well as their cleaning, must be carried out by licensed specialized companies. The check is carried out during any conversion or repair of the system, as well as if there was a lack of traction.

Checking ventilation by anemometer
Diagnostics of the functioning of the exhaust duct is carried out by a special device - an anemometer, which measures and analyzes the air flow rate

The frequency of the scheduled inspection is three times a year (before, after and in the middle of the heating season). Specialists have professional equipment with which they check the operability of the ventilation system.

A pneumatic brushing machine is used to clean the dirt. In addition, channel disinfection is carried out.

Self-cleaning ventilation duct

Despite the existing rules, many management companies do not appear in the apartments of residents for years to check the operability of the ventilation system. Therefore, residents of high-rise buildings are forced to periodically diagnose and clean their exhaust openings on their own.

Cleaning the ventilation duct
With small dirt on the exhaust outlet, you can achieve results with a regular brush

The ventilation hatch can be cleaned with minor contamination, but if the dirt has accumulated in it for years, it is better to call specialists.

Self-cleaning is carried out as follows:

  1. Remove the ventilation grilles, they are well cleaned of dirt and dust and washed under running water.
  2. Cleans the walls of the ductthat you can get to. For work, use a metal brush or wire.
  3. Clean the hole from garbage with a vacuum cleaner.

Actually on this all homework for cleaning the ventilation holes ends. If there is a return draft in the duct and the smells of neighbors reach the apartment, you can replace the old ventilation grill with check valve model.

If they did not lead to the desired result, and the thrust in the channel remained at the same level, then there is a blockage in the common shaft. This is the work of special services that can be called through the Criminal Code.

Professional ventilation cleaning
Licensed companies use professional equipment and special cleaning technologies that are selected after a thorough inspection of the channel and taking into account its current condition

System upgrade to improve performance

In houses of the old construction, mechanical cleaning of the ventilation shaft even by specialized services does not always bring the desired effect. However, it is possible to increase air circulation in the apartment. There are several affordable ways to improve ventilation.

If you decide to replace old wooden windows with modern metal-plastic constructions, choose double-glazed windows equipped with a micro-ventilation function. If you purchased ordinary plastic windows, you can install additional devices on them to ensure the flow of fresh air from the street.

For example, there are ventilating valves, you can additionally purchase special accessories that allow you to tightly close the windows.

Accessories for window ventilation
Accessories for multi-stage ventilation will allow for more efficient ventilation in the apartment

Strengthen the air circulation in the room allows special supply and exhaust fans. There are window, ceiling and wall devices. In the toilet and bathroom you can install exhaust fan right at the entrance to the ventilation duct instead of the decorative grille.

Bathroom fan
The organization of the forced exhaust system, the functions of which are performed by a conventional fan, will help to solve the problem of ventilation in the bathroom.

The fan works from the mains, it can be connected to a common switch and then it will turn on with the light. You can draw an additional line and connect the device to a separate switch so that it works autonomously.

Conclusions and useful video on the topic

How to independently check the ventilation in the apartment, you can find out from the video plot:

What to do if home ventilation does not work well, recovery of the exhaust duct:

How is professional cleaning of ventilation shafts in apartment buildings:

Ventilation has a leading role in ensuring safe living in an apartment. A negligent attitude to this system and neglect of the rules of care can lead to health problems, and for residents of gasified houses it can lead to even more serious consequences.

Therefore, it is necessary to monitor the state of ventilation and, if necessary, contact specialized services.

If you have experience in cleaning the ventilation duct of an apartment, please share the information with our readers. Leave comments and ask questions on the topic in the form below.

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Visitors Comments
  1. Konstantin

    In general, yes, but recently they made repairs in a new building, so there (I was already crouched in surprise) the ventilation was made as exactly the second scheme in the figure, like in the Khrushchevs. And the quality of the house is so-so, in 20 years it will be a wretched shed. What builders do not go to, just to save. And the hood, in my opinion, its performance and the correct functionality, should management companies deal with, there should be a scheduled inspection each, defined by the rules, a period of time, right?

    • Expert
      Alexey Dedyulin

      Good afternoon, Konstantin.

      Builders adjust to market conditions. Potential buyers are trying to find as cheap as possible, and are not particularly eager to “overpay” for a square meter in the presence of a cheaper offer.

      Inspection should be done at least once a year. If necessary, clean the ventilation ducts / chimneys. If reverse thrust is found, they will shrug their shoulders and name a few indistinct reasons and leave.

      In practice, in most cases, UK companies take their responsibilities more seriously only if they have individual heating or geysers in their apartments.

  2. Alexander

    And you do not advise an office phone? And then I called a bunch of companies, the price is very high, it is easier to change the ventilation)) Thank you in advance.

    • Well, you should at least indicate the city in which you live, maybe someone from fellow countrymen would prompt a trusted office. Ask friends or neighbors for sure there are those who cleaned. As a last resort, there are urban communities on the Internet where people exchange experience and advice, ask there.

  3. Sergey Mikhailovich

    Judging by the text of clause 12 of the RF PP No. 410, should preventive cleaning of ventilation ducts, in the presence of traction, be carried out?

    In the Stalinist house, a horizontal prefabricated ventilation box in the attic was made non-separable (the wooden frame is sheathed and there is no possibility to clean the ventilation ducts). I wonder if there is a practice of remaking such boxes into collapsible ones?

    Attached photos:
    • Expert
      Alexey Dedyulin

      Good afternoon, Sergey Mikhailovich. If there is traction, cleaning is not performed.

      Alteration practice exists and is quite successful. Subsequently, it will have approximately the same appearance as in the photo.

      You should contact chimney specialists. They will conduct surveys at the place and offer several options with a clear estimated cost. Most likely, they will offer to install additional turbo-deflectors. You can familiarize yourself with the principle of their work in detail in this article.

      Attached photos:
  4. Stanislav

    Note: ventilation performance, especially kitchen ventilation, cannot be checked with an open flame (lighter, matches, etc.), as dust and grease accumulated over many years of operation burn very well. It’s all checked by a piece of toilet paper. If it sticks to the grate - the ventilation works, it does not stick - write a request to the management company. I do not recommend cleaning the ventilation ducts yourself - you will only make it worse.

  5. Kolya

    The people checking match (fire) stupidity. Do not bring fire to the grill. Dust with fat behind bars - like GUNPOWDER!

  6. How to clean the ventilation duct yourself? Is there a drill and a hammer drill, which nozzles to buy?

    Pressovac washing systems are expensive; you cannot find them on lease. The call of a cleaning company, they want only 3.5 tr for one kitchen. o_O This is very good. expensive!

  7. Victoria

    Thank you for the article. I learned a lot. I called twice in the housing and communal services (Minsk region, Belarus) about the lack of an extract in the bathroom. No answer, no greetings. I will write.

    Mold went in the bathroom and in the kitchen, plastic windows sweat in the inter-heating season, and now. Previously, in the heating season did not sweat. The house is 1962, two-story. After your article, I will search for residential water supply.