Full use of the attic is impossible without proper and effective ventilation of this space.
An attic is a residential attic that needs air circulation, like any living space in a house, but to create ventilation in a house with an attic you should know some nuances.
This room is located above the main living rooms home: bedroom, living room, kitchen, shower room. During human life, heat and moisture are released into the surrounding air, which, according to the laws of convection, rises upward to the ceiling. The ventilation system of the house releases the bulk of the moist air masses into the atmosphere, but some of it penetrates through micro-cracks in the ceiling and ends up in the residential attic.
In an attic that is not equipped with ventilation, moist air masses rise to the ceiling, penetrate through finishing materials and the ceiling, and enter the insulation, and beyond it into the under-roof space. When air saturated with water vapor enters a colder zone, it turns into condensation, which settles on roofing material, insulation and wooden structures, causing them to corrode and lead to their destruction.
Regardless of residential attic space or not, proper ventilation prevents:
- The appearance and accumulation of excess moisture in the under-roof space.
- Wetting of the insulation, which prevents it from losing its thermal insulation qualities.
- Formation of colonies of fungi and foci of mold on wooden elements roofs.
- Corrosion formation on metal elements roofs.
Attic ventilation above the attic prevents overheating during the hot season, and also prevents the formation of ice on roof overhangs in winter.
Features of proper air exchange
Natural ventilation in the space of a residential attic is carried out through supply and exhaust openings, the area of which depends on its area, in the ratio of 0.2 m 2 /100 m 2. The inflow can be carried out through valves installed in the attic windows. Moist air is removed through aerators mounted in the roof plane or at the roof ridge.
By observing the rule of ratio of the area of supply and exhaust openings to the area of the attic space, the attic can be ventilated through the gables. Air flow is carried out through wall supply valves installed in the lower part of the gable, and exhaust through adjustable ventilation grates, mounted in the upper part of the opposite pediment.
Ventilation of the roof and under-roof space is most often done using soffits. This device is nothing more than a perforated panel made of metal or plastic, and intended for covering eaves overhangs. They can be used installed around the perimeter of the house, or alternating with non-perforated panels. 
Soffits can be used as ventilation elements only if, when installing the roofing “pie,” gaps were provided for the movement of air flows along the entire roof.
Methods for ventilating a residential attic
Today there are several main options for ventilation systems. Air circulation can be natural or forced. The natural movement of air masses occurs due to the difference in temperature between atmospheric and internal air. Forced movement is carried out using fans, supply and (or) exhaust.
- Most simple option is the use of natural inflow and exhaust of air mixture from the attic floor. This type of air exchange is most often chosen by those who do their own attic ventilation.
- If the attic geometry is complex, you can use the method of creating in its space overpressure using forced inflow. Thanks to this solution, the supply air masses will displace the exhaust air masses through natural exhaust openings, aerators, etc.
- With short exhaust ducts, they may not have sufficient draft to effective removal air from a residential attic. That is why many developers equip hoods with fans. The influx of air masses, in this case, can also be carried out as with natural movement air flow, and with forced.
- The most complex ventilation system is the mechanically driven system. With this solution, powerful exhaust fans, which are mounted in the space above the attic. The air flow is carried out by supply fans mounted in the openings of the gables.
To ensure that the created forced ventilation system does not create discomfort, you should know that the performance of the exhaust fans must be equal to the performance of the supply mechanisms.
It is obvious that for comfortable life needed in the house efficient air exchange. Today we will talk about how to improve ventilation in the attic - a very specific area.
The attic, a room under the roof, receives warm air saturated with water vapor from the lower rooms. It not only creates discomfort, but also poses a threat to the wooden roof structure and fiber insulation. When it enters a cold zone (under the roof), steam turns into condensation and moistens materials that do not tolerate the effects of water well. Therefore, to remove moist warm air, you need to provide an exhaust hood.
Air exchange can be natural (air moves by gravity due to draft) and forced (due to an electric fan).
There are four main solutions for ventilation:
- with natural inflow and exhaust;
- with forced inflow and natural exhaust;
- with natural inflow and forced exhaust;
- with forced inflow and exhaust.
The first option is the cheapest. In this case, a continuous supply of fresh air is provided by window or wall supply devices (valves). Built into the window, they ventilate the room when the sash is closed. Window valves There are both for ordinary and for skylights. Moreover, attic rooms boast labyrinthine channels that prevent the formation of drafts. But their productivity is small - up to 30-50 m³/h. There are also models with a window valve combined with a handle for opening the sash.
But for wall valve you will have to make a hole in external wall. This device consists of an air duct pipe with a diameter of 80-160 mm, an air intake grille that is installed outside, and a head with an air flow regulator mounted from the inside. The operating principle of the valve varies. For example, in humidified models, a moisture-sensitive sensor located in the room is connected to an external damper. It changes the flow area depending on the level of humidity in the room, thereby controlling the air flow.
As for the hood, it is organized using ventilation ducts, which are laid inside the building during the construction stage. The inlets are made under the ceiling, where heated air accumulates, and the outlets are on the roof.
It is recommended to make the outlet openings of the ventilation ducts as close as possible to the ridge. This is necessary to improve traction.
A system with natural inflow and exhaust has a big drawback: it is effective only in the cold season. The fact is that air circulation requires a large difference between the temperature outside and in the building, which cannot exist in the warm months. A system with natural inflow and forced exhaust does not have this drawback. It involves the use of the same supply valves (wall and window). However, the exhaust is carried out by mechanical fans built into exhaust ducts. Let's take a closer look at them.
There are ready-made products - waterproofed exits ventilation pipes on the roof with a fan inserted into the head. There are also cased exhaust fans with a capacity of 80 to 7000 m 3 /h, mounted in “mini-attics”. This means that they remain between the horizontal ceiling of the attic space and the ridge of the roof. Moreover, the inlet openings are closed with grilles with adjustable dampers, which allows you to control the volume of warm air removed and thereby save heat. Such exhaust fans operate with low noise levels and are not audible in residential areas. In addition, they have minimum consumption electricity, which means their work won’t cost a pretty penny.
Another option is the so-called hybrid ventilation. In this case, there is a mechanical fan on the natural exhaust ducts low pressure. During the cold season, it does not work, and its blades are designed so as not to interfere with natural draft. However, in summer it turns on, maintaining a pressure in the channel comparable to natural draft.
Completely forced ventilation is an expensive solution and, according to many experts, hardly justified in a country house.
To conclude the topic, we note that completely forced ventilation makes sense only when Vacation home is located near a busy highway or is inhabited by people suffering from allergies. In other cases, you can look for a compromise solution to really breathe clean air, and not by forcefully entering the rooms, passing through a mechanical fan (with lubricant), a filter (clogged with dust) and air ducts that are not impeccably clean.
In multi-storey residential buildings, which are built using various building materials, it is necessary to ensure constant ventilation of all rooms and premises. This need is especially relevant when using double-glazed windows in the house, which provide thermal insulation of rooms and good tightness.
Inflow and complete outflow of air is necessary to ensure cozy conditions accommodation. Among other things, in this case the conditions of sanitary, epidemiological and hygienic standards are met, because carbon dioxide and its derivatives formed during life processes are negative factors contributing to the emergence of various bacteria.
By what means can ventilation of rooms be ensured, and how should it be designed? ventilation in two-story house ? This will be discussed in the article.
Ventilation in a private two-story house - Types of ventilation
Selecting a ventilation system carried out at the initial stages of designing a house, as well as taking into account the household or economic load on the premises. Important take into account the location rooms and the overall square footage of the house.
To achieve the assigned tasks, we use following types ventilation:
- With the combined type, air flow is realized naturally and when using mechanical devices. This method is the most common. However, in order to achieve stable ventilation in a private two-story house, must be mounted in walls exhaust ducts of various sizes. Separate boxes must be used for the kitchen area, shower or boiler room. With this method, air masses move naturally. You can also go to the central shaft install a fan, which will accelerate the outflow of air. The advantages of this method include that unpleasant odors do not penetrate into the house, as well as low noise level when the fan operates. The disadvantage is that it is necessary to install flow grilles at the bottom of the doors.
- Natural. Not intended to be used mechanical means to ensure air circulation. Outflow and inflow are carried out due to the difference in air temperatures between the room and the street. This type is used everywhere, but has a number of disadvantages.
- Forced exhaust. Such ventilation system two-story house combined with natural. Air supply can be achieved using installation of special valves or in a natural way, and air is removed from the premises forcibly. For this purpose, they are installed in the bathroom or toilet exhaust fans forced type. The operation of such a system can be automated.
- Supply. To implement this type of air exchange in load-bearing wall or window frames mounted special valve, which carries out forced air flow into the room. You can also use a supply fan to level out the supply of cold air in winter; the system is structurally complicated by adding a heater. Among other things, you can use monoblock complexes that combine a heater, valve, filters and coolers. The equipment can be equipped with a timer, so each owner can set the required response period.
- Forced supply and exhaust. The process of outflow and inflow of air masses is ensured through the use of productive equipment. To the features forced ventilation refers to the fact that it is local when supply equipment installed in areas where it is most needed. With a centralized scheme, one fan is used, located in the central shaft, to which all exhaust ducts are connected.
Ways to create forced or natural air movement there are a lot, so each owner independently chooses the most optimal method.
Natural ventilation of a two-story house
To create all the conditions under which uninterrupted operation of the system will be achieved, several requirements must be met, in this case natural ventilation of a two-story house will have good performance.
When constructing ventilation ducts, vertical shafts are used. One side of the system is installed indoors, and the other is mounted just above the roof ridge. Air movement is ensured through traction, the indicators of which depend on:
- Temperature differences between the room and the street, i.e. at the exit and entrance to the mine.
- Wind, which can improve or worsen draft.
- The geometric cross-section of the channel and its height.
- Thermal insulation characteristics of the shaft channel.
- On the spatial location of the mine (absence or presence of bends and turns).
On initial stages designing a house, the architect chooses the type ventilation and its spatial location inside the building, and at the time of approval of the standard graphic plan, the customer is provided ventilation in a two-story house diagram, which clearly shows all the features and nuances.
Ventilation of a two-story house with your own hands - Calculation of ventilation in the house
All operations for calculating air circulation systems are performed in order to determine the cross-sectional area canals and mines. For this purpose the position SP55.13330.2011., which fully and succinctly specifies standards for air exchange.
- Minimum system performance indicators must provide within an hour one shift the total volume of air in the room (relevant for rooms where people are regularly present).
- From the bathrooms within an hour should be removed at least 25 cubic meters air. From the kitchen at least 60 cubic meters.
These are the main provisions of the rules. You can always get acquainted with them via the Internet. Such standards are publicly available. It is especially necessary to study them carefully for those owners who will independently lay shafts, exhaust ducts and install equipment so that the ventilation functions stably and correctly. two-story house with your own hands, which directly affects comfort.
Ventilation system for a two-story house - Optimization of ventilation
When designing air circulation systems, care must be taken to install specialized equipment:
- At the entrance to the mine install an automatic ventilation valve, which will contain a humidity sensor, which will provide savings in the operation of the system. As the humidity in the room increases, the valve will open wider, which will improve draft.
- All residential premises should arrange valves equipped with sensors outside temperature. In this case, you can level out the flow of cold air, which will allow you to maintain the required temperature balance.
- For free air circulation Between rooms, flow openings with an area of at least 200 sq.cm should be installed.
Please remember that installation fan significantly reduces throughput mines, so this solution is a short-term measure to ensure air circulation. Similar equipment is kitchen hood, since it works for a short time and its use cannot fully provide ventilation of the room.
02.02.2012, 08:32
There are plenty of ways to heat the second floor with a stove. But I want to discuss one more thing.
The Internet is full of reviews where they say that they do not make any additional devices for heating the second floor at all. Warm air itself goes upstairs through the staircase. There are even reports that heat is lost too rapidly to the second floor, which leads to uneven heating: it’s too hot at the top and too cold at the bottom.
The idea is that, without making any special devices for heating the second floor, you can achieve optimal temperatures It's just a matter of adjusting the ventilation.
So far the design appears to be like this. Each room above should have a pair of air ducts: one from the ceiling of the first floor to the ceiling of the second, and the second from the floor of the second floor to the floor of the first, closer to the furnace firebox. The flow-regulating grid can be placed on any of the pipes - the effect should be the same.
The mechanism is as follows. Fresh dry street air is sucked in through the underground and the cracks between the stove and the floor, the surface of the wall heats this dry air, it rises to the ceiling of the first floor and from there it partially reaches the ceiling of the second floor. There it pushes the damp, polluted, cooled air down and through the second air duct directs it to the furnace firebox, from where it is discharged outside.
The question regarding the necessary and sufficient sizes of air ducts is still unclear to me.
02.02.2012, 08:54
By the way, electronics lovers can install automatic controls on the control grilles, which will monitor the equalization of temperature on the ground floor and in different rooms second. And if the second floor is not used, simply block it off, or work in defrost mode.
Grandfather Jedi
02.02.2012, 14:46
zttt, Let's draw?
02.02.2012, 15:06
02.02.2012, 15:25
won't it be hot?
2nd floor is hot, 1st floor is cold
02.02.2012, 17:19
I don’t understand how the air from the floor of the 2nd floor will get into the furnace vent without being disturbed by the air of the first floor.
Andrey Dachnik
02.02.2012, 17:59
Cold air is heavier and will sink, displacing warm air.
02.02.2012, 18:16
Good question. I even began to imagine the whole process a little better while I was thinking about the answer to it.
The pressure in each pipe is proportional to the density difference. The density difference is a function of temperature and humidity. If we neglect humidity, then the pipes begin to work when a temperature difference arises between the ceilings and/or floors. Those. such a system should equalize the temperatures in both rooms. If the furnace is running and hot air accumulates under the ceiling, it begins to rise, and the air from the floor begins to be pushed down. If the furnace is not working, but the air near the floor of the second floor has cooled more than that of the floor of the first floor, then the exchange begins again and the temperature equalizes.
If we take into account humidity, the picture will be somewhat more complicated. There will definitely be slightly higher humidity on the second floor. Perhaps this can be overcome by adjusting the height of the pipes, but you need to think about it.
02.02.2012, 18:32
But this is still purely theoretical reasoning.
02.02.2012, 18:48
By the way, in such a scheme you don’t even need to install dampers: the temperature itself should equalize. You just need to ensure the airtightness of the rooms on the top floor. Otherwise the whole warm air will go there, and it will be cold below.
exactly!
TIGHT!
Without this it’s a bit difficult... by the way, there’s also an ambush - warm air under the ceiling on the first floor heats the floor of the second floor... or should we insulate it here too?
although if fans are installed in the air ducts, all problems are solved. but as I understand it, this is an electrically independent concept.
02.02.2012, 20:17
Let the heat flow through the floor. Everything will be settled. I would like to avoid electricity.
03.02.2012, 11:59
I thought some more, did some digital wandering, and this is what comes out.
Flows depend very little on humidity. Within a couple of degrees with a difference in humidity from 0 to 100%.
The air speed in the pipes is quite stable and in most cases ranges from 1 to 3 meters per second. According to snips, no more than 5 m/s. There is no need to install pipes that are too thick. My bedrooms are approximately 25 cubic meters. With a pipe of 150, the air should be completely exchanged in about half an hour.
Both pipes work together only when the room is completely enclosed. In this case, there will be flow if for at least one pipe the temperature at the bottom is higher than the temperature at the top.
If the door is opened, the planned process is interrupted and the heat simply begins to escape upward. If it is warmer at the top than at the bottom, the ventilation stops. That is why you should not make very thick air ducts. So that when open door the air moving upward was slower.
In practice, the problem of upward movement of heat exists with absolutely any type of heating. The good thing about this system is that the heat exchange stops after the door is closed. After this, the stove, which is very powerful and heat-intensive since it must heat two floors, begins to heat only the lower floor. Top floor It gradually cools down on its own, because there are no heat sources there. Thus, gradually everything returns to normal and the temperatures level out.
In general, I really liked the system. If no one finds any obvious mistakes before the summer, then I’ll do just that. We just need to figure out how to isolate the two floors now. There was no door on the stairs.
Finally, a picture of the estimated air speeds in vertical pipe at different temperatures above and below. It depends little on the diameter, in this case it is 150 mm.
401
03.02.2012, 12:09
Well, the problem will not be solved this way. Essentially, a solution to the problem of air recovery through an inconvenient place.
Place a fan in one pipe, you don’t need a second one at all, the air will rise to the second floor anyway. The pipe exits to the furnace and forward. Turn on synchronously with the ignition of the stove. Electricity consumption is minimal; probably ten years of work will exceed the cost of laying a second pipe.
03.02.2012, 12:39
1. If the doors and windows are closed, then air will not flow through one pipe, even with a fan, even without a fan. Don't believe me? Try forcing air into the bottle. You can blow as much as you like, but you’d rather burst yourself than inflate it with warmth.
2. What are you going to do when the power goes out? Or are you going to fence off the uninterruptible power supply system? Well, you see what unexpected expenses arose.
3. The heat itself goes up without any fans. I'm telling you: without fans, the flow rate is 1-3 meters per second. It's simply not possible anymore. And in general, people are complaining that without any radiators or fans, it’s hot upstairs, and downstairs it’s freezing cold. The task is not just to heat the second floor, but also to heat it so that it is comfortable, i.e. the temperature below and above was not much different.
4. In addition to heating, there is a ventilation problem. I don’t really understand how you will solve this with fans. The fans just stupidly mix good and bad air and it will be indiscriminately thrown out into the chimney. In total, it turns out that you will have a disgusting indoor climate with a fan, and the costs of ventilation (heating the exhaust air) will be quite considerable.
Grandfather Jedi
03.02.2012, 12:46
Electricity consumption is minimal; probably ten years of work will exceed the cost of laying a second pipe.
TB 10 (80 m3/h) - 20 W. So consider it.
True, there is no pressure in the air duct...
402
03.02.2012, 16:52
once again - in rattling rooms (or the entire 2nd floor), the system will work. if they are not airtight, it is hot on the second floor, cold on the first floor.
the cold at first can be overcome due to “radiant heating” from the stove. but the heat on the second - no way.
Grandfather Jedi
03.02.2012, 17:00
I’m glad that we got to this point before anyone invested their soul and money.
03.02.2012, 18:51
As I understand it, air must be supplied to the stove, which is already stale and spoiled, but where fresh air comes from is not discussed at all. The stove de facto burns even without pumping air.
The option of spontaneous mutual replacement of air between floors seems unrealistic, because there is always a way for warm air bypassing the pipe. Sealing floors belongs to the category of science fiction and nonsense. It’s also forbidden for children to run from floor to floor, because it’s not good...
Let’s say a pump, of course it won’t be able to pump 80 cubic meters per hour through a pipe, but the stove doesn’t need that much, because it’s not turbocharged, but regular.
The option of turning off the electricity while firing the stove is not critical, it will be heated anyway :). It seems more likely that it is not a power outage, but a lack of firewood.
03.02.2012, 19:03
the cold at first can be overcome due to “radiant heating” from the stove. but the heat on the second - no way.
This is exactly what I discussed in my answer above. Read it again carefully.
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I'll just add...
1. Tightness is a relative concept. It is enough to keep the doors closed.
2. The system itself comes into balance after closing the doors, even if it became hot upstairs due to the forgetfulness of household members.
3. In radiator heating, the problem of a hot second floor will not go away. It is the nature of warm air to rise. So you still need to isolate the second floor from the first with any heating system.
I actually found a catch, but it does not apply to this system. I just recalculated the heat loss again and it turns out that at -15 (the most common temperature) I will have about 4.5 kW, and at -35 (sometimes it happens) already somewhere around 7.5-8 kW. A stove with such parameters will not fit into the provided space (1.5x1.5m).
For now I’m looking towards the 16kW KIKsP. But I don’t like it because its heat-accumulating properties will be somewhat worse due to the lower temperature in the register area.
03.02.2012, 19:09
In general, it’s some kind of salad, well, at least read what the topikaster is talking about.
This primarily applies to you. Namely:
And where fresh comes from was not discussed at all
The first post in the topic:
The mechanism is as follows. Fresh dry street air is sucked in through the underground and the cracks between the stove and the floor, the surface of the wall heats this dry air...
The pump is only needed when the stove is heating up; the rest of the time it doesn’t really do anything except stir the air.
The option of turning off the electricity while firing the stove is not critical, it will be heated anyway
03.02.2012, 23:33
This primarily applies to you. Namely:
The first post in the topic:
In general, you have learned to criticize, now it’s time to learn to understand what you criticize.
It will be drowning. Only without electricity, the temperature on your first floor will rise to 60 degrees and all residents will suffer heatstroke if they do not retreat in time.
Well, okay, I missed that the air was coming from the floor, although this option in itself looks gloomy.
But about 60 degrees, it’s rare nonsense. Well, there is no electricity, open the doors (or are they electric?) and the heat will go upstairs.
In general, okay, the topic is far-fetched and uninteresting.
Grandfather Jedi
04.02.2012, 03:51
Air from the underground into the firebox is a successful and very common option. All you need is a gate
04.02.2012, 14:24
Good afternoon everyone!
I’ll make a reservation right away that I’m not particularly good at all sorts of formulas (sem heat, conduction heat, etc.). This is what I am ALL ABOUT!!! Interested! During combustion (combustion), air (oxygen) is needed, which is taken from the room in which the stove (boiler) is located, and it enters this room (by suction) from the street! That is, passing through everything that is not dense (doors, windows) is heated room air(thereby cooling it!!!). The stove intake is sucked into the air and flies out into the chimney!!!
The question is this: If we make a two-flow system for supplying air to the boiler??? Thus, we will achieve a closed air flow system (street - boiler - streets) and not (street - apartment - boiler - street)!!! We will get that the apartment will become like a thermos to hold warm air in itself and not filter it through itself!
Is such a system feasible? Its pros and cons???
For greater clarity, I drew a small model of the operating principle of the system.
Please write what you think about this! Thanks in advance!!!416
04.02.2012, 20:11
This perpetual motion machine. In terms of energy, you will not save on this.
The temperature of the exhaust gases should be about 120 degrees, otherwise condensation will form in the pipes. All modern ovens and the boilers are quite capable of providing exactly this temperature without any distortions with counterflows.
Now about double-circuit. In any case, the furnace requires air to operate. It is heated in the oven, which wastes energy, is burned and thrown out into the street.
Now you are isolating the flows to the furnace and inside the house. The air inside the house needs to be changed in the same way, since the residents saturate it carbon dioxide and water vapor. Those. you again need to suck in air from the street, heat it again and throw it out into the street again. As you can see, in this scheme the air is heated twice, whereas in the case of a stove only once.
In fact, double-circuit (without countercurrent) is used almost always when the boiler is located outside the heated room. Heating plants also burn fuel and air, which requires energy to heat. And in any room that is heated by a heating plant, ventilation operates, which again heats the air and again throws it out into the street.
Make the ventilation system in exactly the same way! In two streams! So, as far as I know, they do it in new energy-saving houses
This is called recovery. IN stove heating there is no point in it, because the air is not released into the street, but only smoke is released.
Nowadays there are a lot of people against the air from underground - like radon there is a hell of a lot, and therefore it is better to isolate the house from the underground if possible.
In fact, it is customary to ventilate the underground. And if you are afraid of radon, then the underground should not be made of earth, but at least the floor should be concreted. In any case, radon is a much less evil than a fan whirring in the room around the clock :)
From the author: Hello, Dear friends! It has long been known that a properly equipped ventilation system is the key to comfortable and healthy life. After all, the microclimate is of great importance. That is why today we will talk about how ventilation is installed in a two-story private house.
Strictly speaking, the design of the system does not change much depending on the number of floors. The only difference is that when using forced ventilation it is necessary to use more powerful equipment for a two-story cottage than for a one-story one. This is due, first of all, to the volume of air available in the house.
In general, the methods are not too different. And certainly for a house of any number of floors it is necessary to approach the issue equally competently. Oddly enough, among some owners of country houses there is an opinion that private buildings do not need special established system air exchange. Such doubts arise especially often if the house is built from “breathable” materials - for example, wood.
But let's evaluate the overall picture objectively. Think about it, because you are unlikely to leave the erected walls bare. An insulating layer will probably be placed on them, and then a finishing touch, giving the building a beautiful and aesthetic appearance. All of these additions will definitely block access to fresh air that might otherwise pass through the walls.
Even if you are going to build a house from wood, which does not require finishing, please note that modern timber has completely different qualities than the wood that was used in the good old days. Now the material is impregnated with various compounds designed to protect it from harmful effects external environment. In addition, the timber is often glued. All these substances tightly clog the pores, so there is simply no opportunity for air exchange.
Also, do not forget about double-glazed windows, which are installed on windows everywhere. Previously, ordinary wooden frames with glass. They had wonderful gaps in their design, through which fresh air successfully circulated towards the house and back.
In general, arguments in favor of arrangement ventilation system so many. Let's finally begin to consider what methods can be used to organize this.
Type of ventilation
First of all, it is worth understanding the two types of air exchange. It can be natural or forced. Each option has certain advantages and disadvantages, so let's take a closer look at them.
Natural air exchange
Natural ventilation is ventilation that does not require the installation of any equipment designed to stimulate air movement. Simply put, air masses lead a completely independent life. To remove exhaust air, ventilation shafts are provided - in other words, channels cut into the ceiling and wall that go out onto the roof.
The air that has been in the house becomes warm. As everyone knows from school physics lessons, in this case it begins to rise upward. This is what they are designed for, the entrance to which is located in the upper part of the room. Air masses reach them naturally, and then follow up the shaft, emerging from the pipe into the street.
This is all clear. But as you know, the amount of air that leaves the house must somehow be replenished. And this is where the problem lies. It has already been discussed in detail above that modern walls and double-glazed windows make the home a real fortress, into which the enemy may perhaps penetrate, but fresh air certainly does not.
The problem can be solved in two ways:
- ventilation. Everyone seems to know how this is done - if the house becomes stuffy, you need to open the window. In fact, when stuffiness sets in, your brain has already begun to get tired and experience oxygen starvation. This should not be allowed, since frequent repetition of such situations can seriously harm your health. For example, this is fraught with migraines - rather unpleasant conditions that are difficult to get rid of. So, in order not to lead yourself to oxygen starvation, you need to do ventilation not after the onset of stuffiness, but at a certain frequency - every three hours. The duration of the procedure is 15 minutes. The problem is that not every family has a person who would agree to sit at home all day long and periodically open the window. As a rule, most people work, so in the evenings they have to return to their homes with stagnant air;
- use of an inlet valve. This simple equipment is an excellent alternative to ventilation. The supply valve is installed either in a window or in a wall. It essentially consists of an air duct through which air masses circulate. The equipment is made in such a way that its installation does not in any way affect the occurrence of drafts or changes in temperature in the home. Thus, there is no need to constantly open the window - through supply valve freshness and oxygen are supplied continuously.
But even the use of a supply valve cannot solve main problem natural ventilation. We are talking about low air exchange rates. The fact is that, regardless of the method of fresh air supply, it depends on certain external factors. First of all, it depends on the air temperature outside and inside the room.
To ensure at least a relatively normal air exchange rate, it is necessary that it be cold outside and hot in the house. The smaller the temperature difference, the slower the air exchange occurs. What then happens in the summer, when it is equally hot outside and indoors? Never mind. There is simply no air exchange, or there is, but at such a level that there is no point.
In principle, natural ventilation may be more or less suitable for small houses - there is a small volume of air, the change of which does not take much time. But since today we are talking about two-story buildings, we immediately reject this option for the reasons described above.
Forced air exchange
But this method is the one that is suitable for consideration for use in a private house of any number of floors. In this case, air circulation is affected by the use special equipment, which is installed either in the shaft, or on the roof, or in one of non-residential premises- for example, on the attic floor. There are also free-standing devices, which will be discussed below.
Forced ventilation options
Arrangement compulsory system air exchange is a fairly broad topic, so it is necessary to consider it in as much detail as possible. Let's start with the fact that this method is divided into three types: supply, exhaust and supply and exhaust ventilation.
Supply equipment
Supply ventilation equipment is responsible for pumping fresh air into the house. In this case, the waste material comes out naturally through the same exhaust shafts. This principle is based on the difference in density of cold and warm air.
The first, entering the room, has a denser structure due to its temperature, it is heavier and is located first in the floor area. Due to these properties, it pushes out already heated exhaust air masses. They rise up and go outside through the ventilation ducts.
Then the process is repeated. Cold air comes in, old air comes out. In general, natural ventilation works on the same principle. But the forced one has a high discharge rate, due to which the intensity of air exchange increases sharply.
There are two most popular types of devices for equipping such a system:
- supply valves. Yes, they have already been mentioned in the conversation about natural air exchange. But in this case, these devices also have a fan in their design, which is responsible for pumping air into the room. Despite this, the device still remains quite simple. An air duct is laid inside the wall into which the fan is installed. On the side of the room, the structure is closed with a lid, and on the outside of the building - with a protective grille, the purpose of which is to create a barrier against precipitation, debris, small rodents and various living creatures that have absolutely no business in a decent house. Installation of the supply valve is very simple: just drill the wall using a hammer drill, then clean the hole, place the air duct in it and assemble the entire structure;
- breather Essentially, this is the same supply valve, but with expanded functionality. There is also an air duct, a fan and protective grilles. But they also come with some “chips” that are responsible for the comfort of the people living in the house. For example, these include temperature and humidity sensors, with the help of which equipment can automatically start when necessary. In addition, many breathers have a small convector built into them, which heats the air entering the house in the current mode. Thus, the temperature level in the room does not change in any way - this is both comfortable and allows you to save on heating resources.
Exhaust equipment
Another option for arranging a forced ventilation system is the use of exhaust equipment. It is installed, as a rule, in places with an increased need for air removal. This, of course, is a sanitary unit and a kitchen area.
In the first case, the need is mainly due to high level humidity. If you don't fight it in any way, then over time it will lead to damage. finishing materials, as well as to the formation of mold, which is directly harmful to health.
The kitchen also needs to remove air for obvious reasons: it is both grease and high humidity, and not always pleasant smells. Moreover, sometimes it happens that the food is burnt, and it is necessary to get rid of these aromas as quickly as possible.
For such cases, a kitchen hood is installed - equipment that is located above the stove and connected to the ventilation shaft. There is a fan inside the device, which is responsible for drawing in and further removing air masses along with odors and humidity.
In the bathroom and toilet, the role of exhaust equipment is also performed by a fan, which is installed at the entrance to the ventilation duct and is covered with a protective grille. It helps to quickly normalize the humidity level in the room.
The disadvantage of an exhaust forced ventilation system is the same modest volume of arriving fresh air. This has already been said more than once today, so we won’t repeat it. But the problem will not go away. Especially it concerns two-story houses, in which the volume of air is quite large. It simply won’t have time to replenish itself. Therefore for this case It is worth considering the third method of arranging a ventilation system.
Supply and exhaust equipment
From the name it is clear that the devices installed within such a system are responsible for both the supply and removal of air. Most often this is achieved by combining various devices. For example, you can install breathers, and install exhaust devices in the kitchen and bathroom.
This approach solves two problems at once. Firstly, the required air exchange rate is achieved. Secondly, you can completely control the volume of both incoming and outgoing air masses.
In addition, there are special double-acting devices - supply and exhaust. As a rule, they are equipped with recuperators. This item is designed to hold thermal energy from recycled air and give it to fresh air upon arrival of the latter.
Agree that such savings on heating in big house very useful. You will kill two birds with one stone: you will gain a healthy microclimate, and temperature regime Do not disturb the premises in any way.
Certainly, supply and exhaust ventilation costs an order of magnitude more than other systems. Firstly, the equipment itself costs a lot. Secondly, all devices are connected to the mains and consume a certain amount of electricity during operation.
The last factor, by the way, is the main disadvantage of forced ventilation, regardless of what type of ventilation is used. Dependence on electricity means that in the event of a power outage, all equipment will simply stop.
So it is recommended that you consider purchasing and installing a backup generator in advance. It will be useful to you to maintain the performance of not only ventilation, but also heating system in case of force majeure.
As for the installation of equipment for forced ventilation, it is not that complicated. You can read about how to properly do the installation yourself in articles on our website dedicated to this topic. After receiving necessary information you'll do great. Good luck!
