Aerated concrete in recent years has gained wide popularity. More and more people are choosing this material for the construction of their homes. It attracts with an affordable price, excellent technical characteristics and technological advantages: work with it progresses much easier and faster than with brick.
Often, the owner of a new house primarily considers it necessary to conduct electricity, heating, water and sewage into the house, forgetting or deliberately pushing the ventilation system into the background. So is ventilation in a private house of aerated concrete necessary? And if so, which one is better to choose? Yes, and how to do it?
You will learn all about the value of the ventilation system in the house from aerated concrete blocks from the article we have proposed. We will introduce the types and specifics of the organization of communications that ensure stable regulatory air exchange. Let's talk about the features of their device.
Why is ventilation needed?
For a comfortable stay of a person in a work / residential / utility room, certain microclimate parameters must be supported: lighting, temperature, humidity, oxygen, carbon dioxide concentration, permissible percentage of airborne pollutants, etc.
You probably noticed that sometimes even at a comfortable temperature we feel stuffy, damp and uncomfortable. Smells from the kitchen or bathrooms scatter throughout the house and do not disappear for a long time, and in the rays of sunlight, countless dust particles are visible. Unfortunately, many homeowners are familiar with these situations.
Without a properly functioning ventilation system providing regular air exchange, it is impossible to achieve the microclimate parameters required for a comfortable and safe living environment
The cause of all these troubles in most cases is a malfunction or lack of a ventilation system. After all, it is she who is responsible for removing the exhausted air mass from the room and supplying him with a fresh and clean stream.
Since school, we know that in the process of breathing and vital activity, a person consumes oxygen and releases carbon dioxide and moisture into the air surrounding us. Also, a lot of moisture gets into the air when washing and drying clothes, cooking, wet cleaning, taking a shower.
It is better to build a ventilation system with risers located in structures during the construction process. However, if her organization was lost, then ventilation is not too late to do after finishing work
We constantly, without thinking about it, bring home dust on clothes and things. The atmosphere within confined spaces is literally teeming with volatile microscopic organic and mineral contaminants, animal hair.
If the house does not have a ventilation system, then all moisture, dust and CO2 accumulate in the air. In this case, the amount of oxygen, on the contrary, decreases, making our stay in the room unbearable. If you ignore this state of affairs for a long time, then you may experience problems with well-being and health.
Regular air exchange is carried out through the intake of air from the street through the supply components and the exhaust air mass through the exhaust hood
Without a stably set air exchange in a house with walls, condensate will not be removed from the aerated concrete blocks in a timely manner. As a result, a fungus settles in building structures, destroying both building materials and the health of owners with households.
Sanitary regulations for ventilation
Unlike private developers, employees of design organizations and sanitary doctors are well aware of the importance of air exchange in residential buildings. Therefore, ventilation along with heating, water supply, and lighting are devoted to entire sections of regulatory documents.
Here are some of these rules:
- SP 13330.2016 Heating, ventilation and air conditioning. Updated edition of SNiP 41-01-2003;
- SanPiN 2.1.2.2645-10 “Sanitary and epidemiological requirements for living conditions in residential buildings and premises” (Section IV. Hygienic requirements for heating, ventilation, microclimate and air environment of premises);
- “SNiP 2.08.01-89 *. Residential buildings ”(Section 3. Heating, ventilation and air conditioning. Appendix 4 (mandatory). Design air parameters and air exchange rate in the premises of residential buildings).
Briefly, the requirements of these rules look like this:
- All residential buildings must have a ventilation system;
- The ventilation system with a specified frequency should ensure the replacement of exhaust air with fresh;
- The air outlet from the premises of a residential building should be provided through the exhaust ducts of kitchens, latrines and bathrooms (showers).
But such standards for the amount of air removed are established by the rules:
Room | The amount of air removed from the room |
Living room | 3m3/ h at 1 m2 premises |
Kitchen with electric stove | Not less than 60 m3/ h |
Kitchen with 2 comfortable gas stove | Not less than 60 m3/ h |
Kitchen with 4 comfortable gas stove | Not less than 90 m3/ h |
Bathroom | Not less than 25 m3/ h |
Restroom | Not less than 25 m3/ h |
Combined bathroom and toilet | Not less than 50 m3/ h |
Let's calculate the volume of air exchange for a two-story house with four rooms with a total area of 80 m2, two combined bathrooms and a kitchen with a 4-comfortable gas stove:
Standard for rooms = 80 m2 * 3m3/ h at 1 m2 premises = 240 m3/ h;
Standard for the kitchen = 90 m3/ h;
Standard for bathrooms = 2 bathrooms * 50 m3/ h = 100 m3/ h
TOTAL: 430 m3/ h
It is such an air exchange that is required to be provided in our conditional house for a comfortable state of health and to maintain the furnishings in good condition.
The ventilation system is required to divert and supply exactly the amount of fresh air that is required by sanitary standards. Excessive air exchange can reduce the humidity necessary for breathing, which will have to be restored mechanically
Concluding the topic of standards, it should be noted that it is important not only to achieve normative air exchange, but also not to overdo it. After all, the greater the air exchange, the higher the speed of the air flow through the rooms, and if its values are excessive, negative phenomena can occur - drafts.
Ventilation schemes for houses made of aerated concrete
In general, ventilation systems can be divided into two main groups - natural and forced (mechanical).
Natural scheme It works due to the temperature difference and the density of the air mass inside and outside the building. It is completely autonomous, operates independently of the supply of electricity. However, the closer the outside temperature to room temperature, the worse the air exchange will be, up to a complete stop.
This is especially felt in the summer. To achieve high performance in natural ventilation is problematic. Especially if it is arranged according to the channel principle with numerous twists and turns: the more complex the scheme, the weaker the thrust;
Mechanical circuit much more powerful than the natural system. It is often supplied with additional functions of heating or cooling the air, the function of heat conservation (recovery), the ability to integrate into the Smart Home system. Such ventilation works regardless of temperature changes.
Both types of systems are united by the fact that it is desirable to think over both natural and mechanical ventilation at the stage of designing a house and install it immediately, during its construction.
Why is it important? Because the ventilation system, in most cases, is a network of metal or plastic ducts that must be laid out of the premises and brought to the roof.
One of the most popular ways of organizing duct ventilation in houses made of aerated concrete is laying them under the upper ceiling. The system is closed with suspended or suspended ceilings so that only the grilles of the supply and exhaust openings are visible
If you do not immediately take into account all the nuances of installation, then the ventilation device in the future can be fraught with many difficulties (punching or drilling holes in the main walls and floors, the need to lay pipes from the premises of the first floor through the living rooms of the second, ugly appearance, etc.).
Despite the apparent complexity, it’s quite simple to understand the organization’s issues in order to mount the ventilation in a gas concrete house with your own hands or competently order its installation without overpaying for equipment and work.
So, let's move on to the types of ventilation.
Subtleties of a natural ventilation device
We have already figured out that the force that makes natural ventilation work is the desire of warm air to rise up. In order for such a movement to begin, an air duct is needed that allows warm air from the room to exit onto a colder street.
Air ducts are made of plastic, metal galvanized or stainless round pipes or profiles of square or rectangular cross-section. Also ventilation ducts can be made in the form of voids in the walls during their construction.
If the above pipes are laid in such voids, then this is called shelling, this method is widely used, since it eliminates masonry leaks and facilitates maintenance.
With natural ventilation, air ducts are made vertical and as straight as possible, and the number of turns and horizontal (inclined) sections is minimized, as this reduces traction. Also, for better traction, you can not narrow the diameter of the pipe.
The ventilation risers of the exhaust part of the natural ventilation are displayed above the roof to a height equal to the height of the chimneys. If the distance between the ridge and the ventilation pipe is less than 1.5 m, the pipe should rise at least 0.5 m above the ridge ridge. This is necessary to form a stable draft
Exhaust openings are supplied with ventilating grates. They are installed in the upper quarter of the walls or directly under the ceiling, since it is there that air rises, requiring removal.
The air flow in natural ventilation schemes occurs through leaks in building structures, windows and doors, as well as through special air inlets located at the bottom of the house.
Plastic windows and safe doors practically do not let air through. Therefore, when installing natural ventilation in modern housing, the presence of air inlets or valves is a prerequisite for the operation of the ventilation system.
The simplest solution is to install windows with ventilation valves. They will allow without the production of additional holes to ensure the flow of fresh air into the room.
To equip a house from aerated concrete, it is better to buy double-glazed windows with an integrated micro-ventilation system. So it will be possible to ensure a continuous flow of fresh air into the house without noticeable drafts
But do not despair if the windows in the house are installed without such valves. For these cases, wall mounted devices are available on the market. They have a much larger throughput than window ones, and can also be equipped with filters, which allows you to clean the air before it is fed into the housing.
It is worth remembering that wall valves cannot ventilate a room on their own. For their work, a built-in exhaust or supply fan should work. The valves simply let air from the street through them and allow you to adjust its flow by opening or closing the damper.
Wall ventilation valves are divided into supply and exhaust. Supply models are equipped with devices for filtering the air flow. Among them there are models with devices for heating the flow
Natural ventilation is good for its simplicity, low cost and non-volatility. It is easy to carry out its installation with your own hands. It can be a great solution for small houses.
The nuances of organizing mechanical ventilation
The difference between a mechanical ventilation system and a natural one is that the air is driven by electric fans. Due to this, mechanical ventilation can have a complex and long system of ventilation ducts with both vertical and horizontal sections.
Pressure losses in ducted mechanical ventilation options are compensated by an increase in fan power. This allows air ducts to go into all the necessary rooms without worrying about the lack of traction.
The mechanical version of the ventilation system is completely independent of temperature and air density outside the window and indoors. Its design includes fans forcing air inward or exhausting air through exhaust components
Another distinguishing feature of a mechanical ventilation system is the ability to automate it. Thanks to the installation of fans with multi-stage speed control, as well as other devices that control the speed, direction of the air flow and its temperature, mechanical ventilation allows for optimal air exchange in each room.
It is more profitable to equip a private house with a mixed ventilation system, which includes components of both gravitational and forced type. In these schemes, air movement is stimulated by a fan mounted either in the inlet or in the exhaust.
Mixed ventilation schemes use both gravity principles and mechanical devices. Either inflow or exhaust in them is carried out by a fan
Mechanical and mixed ventilation can be local and centralized.
With a local ventilation system in each room from which air is removed, its own fan is installed. A typical example is a kitchen hood and a fan on the exhaust hole in the bathroom.
Exhaust components of both natural and mechanical ventilation systems are located in the upper part of the wall, because contaminated warm air spontaneously moves up
Such a solution is often used if, for some reason, the draft of natural ventilation was not enough and it is necessary to increase it. Installing local exhaust fans is a low-cost method that you can do yourself.
Both for the natural scheme, and for mechanical exhaust ventilation, the presence of air flow paths through leaks, or through special inlet openings or valves, is mandatory.
With a centralized ventilation system in the house, usually in the attic, an exhaust or supply and exhaust ventilation unit is mounted. Further, from this unit, ventilation ducts are laid into the necessary premises, removing the exhaust air, and if the supply and exhaust installation, then supplying fresh.
It is better to mount the unit of the supply and exhaust ventilation unit outside the living room, as it can make noise during operation. Ideally, accommodate a non-residential attic
Supply and exhaust ventilation units are equipped with two fans and ensure equal amounts of incoming and outgoing air. Also, such plants can be equipped with heating systems and filtering the incoming air and automation, which allows you to maintain the specified temperature and air exchange.
Recovery ventilation units equipped with a device that increases the economic effect of the use of equipment. This is a recuperator that provides the ability to rationally manage the energy of heating systems and save on utility bills.
With any other type of mechanical ventilation, heat is simply emitted from the room to the street along with the exhaust air! Savings from ventilation with recovery are especially relevant in the winter, when a lot of thermal energy flies into the ventilation pipe. At the same time, the cold air coming in from the street must also be warmed up to room temperature.
The recuperator is a heat exchanger through which warm air from the house and cold air from the street pass simultaneously. In some models of recuperators, additional plate heaters with freon or water are used.
In ventilation systems with a recuperator, the warm air from the room is cleaned and mixed with the fresh portion captured by the fan from the street
Thus, fresh air is not heated by heating or electricity, but by previously heated air removed from the room. Heat losses in the case of a recuperator are minimal.
In warm times, when it is hot outside, the recuperator is also useful: in this case, it cools the hot air coming from the street with cooler air from the room, reducing air-conditioning costs.
Recovery is a technological process of reuse of thermal energy, which can significantly reduce the cost of preparing street air pumped by ventilation into the room
Unfortunately, with obvious advantages, recovery has two drawbacks:
- Firstly, ventilation units with recovery cost several times more than similar installations without a recuperator;
- Secondly, recuperators can only work stably when the street temperature is not lower than - 10 aboutC. At colder temperatures, the plates become icy.
However, even with its shortcomings, a recuperator is the best solution for systems that process all the rooms in the house. Among the local options, the breather is in the lead.
Breather - This is a device for ventilation in a single room. It consists of a ventilation duct and a housing in which are installed: electric heater, fan, filters, shutters and automatic control.
For convenience, the breathers may have a remote control. Some breathers are equipped with a ceramic heat exchanger, which allows them to work in the recovery mode.
The breather is a rather effective local ventilation system in miniature, producing heating and cleaning the air flow
Breathers forcibly pump fresh air into the room, pre-filtering and, if necessary, heating it. Models with a heat exchanger can not only pump air into the room, but also remove the old one from it.
In the house of aerated concrete, the self-installation of breathers and valves does not cause difficulties: you just need to drill a hole of a suitable diameter under the ventilation pipe in the wall and fix the device to the wall.
Ventilation air purification
At the beginning of the article, dust flying in the air with improper or absent ventilation was mentioned. To solve this problem, modern ventilation systems can be equipped with special filters to clean the air entering the room from the street.
At the same time, depending on your needs, the set of filters can be different: from rough cleaning, delaying only large particles; to fine cleaning, not even letting in smells and pollen.
To equip ventilation systems, filters of various levels are produced. Among them there are models for rough and fine cleaning, keeping animal hair, sifting viruses, etc.
There is only one drawback with filters: they need to be changed periodically.
Chimneys of stoves and fireplaces in residential premises
If you are planning or already own a stove or fireplace in your home, then when calculating the ventilation, you need to keep in mind that the chimneys of stoves and fireplaces are actually exhaust ventilation.
In the cold state, the chimneys work like a normal natural exhaust, and when burning wood, this effect is greatly enhanced, since a large amount of air is consumed for burning.
And although chimneys cannot fully fulfill the function of exhaust ventilation, their presence must be taken into account when determining the size of the supply openings so that they can provide the required fresh air flow for both the main ventilation and the heating device.
DIY installation of a ventilation system
Now on the Internet there is any information about the selection and installation of ventilation systems, which in a house from aerated concrete can be built without problems by yourself. At a hardware store, you can freely buy ventilation ducts, fans, or serious ventilation installations.
Various methods are used to mask ventilation ducts. The most popular location behind a false wall or in a drywall box
The only thing that is better to entrust to the designers is the calculation of ventilation, because it is unlikely to be able to do it yourself without knowledge.
Correct calculation is especially relevant if you plan to use natural ventilation, because in this case it is important to choose the right amount and cross-section of ventilation ducts so that they provide the necessary draft and air exchange.
If you plan to install mechanical ventilation, then an approximate calculation of its performance can be done based on the standards, as in the example indicated at the beginning of this article. To do this, you need to calculate the standard value of ventilation for your home and increase this value by 10-20% to compensate for losses during air movement through ventilation ducts.
As for the installation of ventilation itself, for people building a house with their own hands, as a rule, there is nothing complicated.
Ventilation ducts are assembled as a designer when one part is freely inserted into another. A large number of lengths, shapes and sections of the channels, as well as various bends, tees, transitions, valves, gate valves and other products allow you to assemble a ventilation duct of any configuration.
The construction of the ventilation system will be much faster if you use a set of parts intended for these purposes
Also, due to standardization of sizes, ventilation ducts can be connected to a wide variety of supply, exhaust and supply and exhaust mechanical ventilation systems without problems.
The choice of such plants and their manufacturers, by the way, is also great: from budget ones with simple functionality, to premium ones with full automation.
Properly selected and installed ventilation in the house from the gas block is a guarantee of well-being and health of households. Natural ventilation is suitable for small houses, and for large buildings with many rooms, the best solution would be a mechanical system.
You can choose and install ventilation both independently and entrusting it to the builders, but in both cases it is recommended to do this at the design stage (planning) and construction of the house.
Do you want to share your own experience in building a ventilation system in a house from aerated concrete blocks? Please leave comments in the form below the block. In it you can ask questions, post a photo on the topic of the article, give useful recommendations to site visitors.