When building a house or upgrading it, it is necessary to install air ducts. It is rather problematic to live without ventilation, as it allows you to create a pleasant microclimate in the room, to provide residents with high-quality air. Agree that it is much more pleasant to rest and work in a ventilated room than in a stuffy one.
The body always has enough oxygen, various pathogenic bacteria do not multiply, and most importantly, a person does not have a feeling of lack of strength. But in order to make proper ventilation, you need to make calculations for all air ducts. It is also necessary to select components for each room and install them.
If you cannot calculate and install on your own, contact a specialist. After all, people who design and manufacture such systems often will be able to do all the work quickly and efficiently - they already have a full hand. But you have to pay for these services. If you want to save money and learn something new, feel free to start makingventilation.
What are the criteria for choosing air ducts?
First, we'll talk about how to make the right choice of products. After all, the installation of ventilation ducts depends directly on the specific types of nodes used. But to make a choice, you must definitely familiarize yourself with the information about the features of all types of air ducts, their disadvantages and advantages. All air ducts can be divided and classified according to three main parameters:
- According to the material of manufacture (plastic, metal).
- According to design features.
- By section type.
Pay attention to what options the dimensional grid has. Most manufacturers of components for ventilation systems adhere to the current GOST:
- Diameter range 100-2000mm.
- Not more than 20 meters long.
These parameters are basic, but when designing a ventilation system, such characteristics as:
- Section area.
- Duct wall thickness.
- Perimeter value.
- Maximum hydraulic pressure.
It is rather difficult to calculate these characteristics on your own - it is better to contact specialists. They will be able to select the most suitable elements for ventilation according to the set conditions.
Duct Designs
There are only two types of duct construction that are used in practice. If you plan to install ductwork with your ownhands, you need to follow the recommendations of experts. But the most important thing is to choose the right type of construction so that it not only performs its functions, but also harmoniously fits into the interior of the room.
The following types of air ducts are distinguished by design:
- External - installed on the walls. Are carried out in the form of added or suspended boxes. The assembly of such systems can be carried out from shaped elements with different sections, shapes and lengths of air ducts. When installing, first of all, you need to carefully develop a scheme according to which the installation will be carried out. At the same time, the architectural features of the building are taken into account - external attractiveness should not suffer. And air circulation should be as intense as possible.
- Recessed ducts are used when installing the system inside brick or concrete walls. Such structures have one feature - the inner surface of the channels is perfectly smooth, which allows air flows to move more freely inside. Air ducts must have technological holes through which cleaning is carried out periodically.
What materials are air ducts made of?
Depending on what material the components are made from, the installation of the duct system varies. As a rule, lightweight materials are used for the manufacture of such structures - after all, the channels must be fixed on walls or ceilings.
And heavy structures are much more difficult to hold. Standard set of materials forduct fabrication:
- Metals. Usually it is stainless or galvanized steel, aluminum-based alloys. No matter what metal is used, the air duct has a high degree of strength, fire resistance, and corrosion resistance. Moreover, metal components are flexible and durable. But the last parameter is directly affected by the quality of the metal or alloy. As for the cost of products, the cheapest are galvanized. Aluminum will be more expensive, but its resource is slightly higher.
- Plastic. Such air ducts are made on the basis of polypropylene. And this is a material that has high strength, low weight, it is environmentally friendly and resistant to various liquids. But when installing rectangular plastic ducts, one drawback must be taken into account - under mechanical stress, the risk of deformation becomes higher. In addition, plastic products have a very low temperature threshold.
- Polymeric materials are suitable for the manufacture of flexible ducts used in ventilation systems. Corrugated pipes are also made from such compositions. To make the channels as rigid as possible, use steel wire or aluminum. Such reinforcement is able to hold the entire structure and prevent it from deforming. Elements made of polymers can be used both independently and in combination with metal or plastic. But it is imperative that when installing flexible air ducts based on polymers, it is necessary to take into account the fact that the parts have a rather large aerodynamic resistance. In addition, they make a lot of noise when working.systems. Ideally, flexible ducts are installed in small (especially inaccessible) areas. Usually they are used to make bends and branches.
Duct section type
When installing galvanized or plastic air ducts, the main thing is to choose the type of section. There are the following types:
- Rectangular and square. They are used to harmoniously decorate the interior of the premises. The decision to install such structures is justified if the ceiling height is not very large. But there is one drawback - the manufacture of air ducts and their installation will take a lot of time and effort. It is also necessary to take into account the fact that high aerodynamic resistance is observed during the operation of rectangular ducts.
- Absolutely in any ventilation system you can use circular ducts. Installation of air ducts according to SNIP can be carried out from such elements. They are practical, they have very low aerodynamic drag. In addition, they are very convenient to mount, and there are no difficulties during operation.
Now that you know all the features of the air ducts, you can go directly to the installation. There will be no difficulties if you have all the necessary tools and materials.
Ventilation duct installation process
Installation of ventilation is a very serious matter, and it must be approached with all responsibility. The comfort of people staying in the house depends on the quality of the work. Ventilation also has a significant impact on he alth. Before the beginningall work must be prepared. The installation process is as follows:
- Air ducts are being calculated. Moreover, the more competently it is made, the more efficient the system will work in the future.
- The most appropriate type of component connection is selected. There should be no gaps, cracks.
- The type and total number of shaped elements that are installed additionally are determined.
- The correct duct design is selected. You can install additional heat and sound insulation. But this will require additional investments, so if you want to save money, discard these materials. True, there are cases when it is impossible to refuse the use of insulating materials. You can read about it below.
Duct insulation
Now it's time to decide if additional insulation is needed for the ducts.
Our recommendations will help you make the right choice:
- There is a need to insulate if the air duct is installed outside the building or in a room that is not heated. So you get rid of a large number of problems - in particular, from accumulations of condensate on the inner surface of the ventilation system. This will prevent the appearance of fungi and mold in the house. After all, ventilation is done in order to save a house or apartment from these troubles.
- Noise insulation is performed if the air ductsare laid in such premises: work offices, home offices, children's rooms and bedrooms. Depending on the goal, the method of soundproofing is selected. It is also necessary to take into account the degree of comfort and design features.
As you understand, there are several ways to reduce the noise level. But which one is better to use? It all depends, of course, on specific conditions and financial possibilities. It is possible to distinguish the most popular types of soundproofing of ventilation ducts:
- It is allowed to use parts with a large wall thickness or an increased cross section. But this can only be applied in the case of installation of ventilation in spacious and huge rooms. In this case, the total cost of all components will be quite large. Thin-walled have a lower price.
- Installation of special anti-vibration elements - various fans, dampers. It is possible that in this case it will be necessary to change the circuit of the entire ventilation line. The duct will have to be mounted a little differently.
- Winding the pipes of the ventilation system with various soundproofing materials, especially porous ones show themselves well. This is the easiest and cheapest way to install soundproofing, but the appearance suffers, and quite a lot. In most cases, additional decoration of ventilation ducts is required.
How to choose additional parts
Each case is individual, so the use of additional elements will depend on the specific situation. You can also use different amountsand element types.
You can select such parts that are needed for the installation of ventilation ducts:
- Cross.
- Bends.
- Tees.
- Umbrellas.
- Insets.
- Ducks.
- Plugs.
- Transitions.
- Throttle valves.
In the event that you are unable to determine the number and type of parts that are needed specifically for the implementation of your project, contact the specialists. As a rule, sellers in stores that sell air ducts and parts for them have enough knowledge to help you decide on the choice of products. All you need is a plan diagram of the entire structure.
How to calculate duct parameters
Regardless of whether plastic or metal ducts are being installed, certain requirements must be followed. The sequence of work must also be observed. The most important stage is the calculation of the parameters of the air channels. You now need to decide how much air to supply to each room or space.
When installing plastic or galvanized air ducts, this can be done in one of two ways:
- Be sure to take into account the total number of people who are constantly in the room. To do this, you can use a simple formula: L=NL NORM. Let's write this formula to find out which letters stand for what. Here Lis the required performance of the system. N is the number of people living in the room. And L NORM is a standard that shows what is the rate of air consumption per person per hour. For example, in the state of sleep and rest, we consume 30 m3/h. And if you are guided by SNIP, then this figure is twice as high - 60 m3/h.
- You can also use the following formula for calculations: L=nSH. In it, L is a performance indicator (measured in cubic meters per hour), n is a normalized multiplicity value (taken equal to 1-2 for residential rooms and 2-3 for office rooms). H is the height of the ceilings in the room, and S is the area in square meters. Before installing the duct for the kitchen hood, it is also necessary to make similar calculations so that the "bad" air leaves the room as quickly as possible.
It is advisable to perform the calculation using two formulas at once, after which the largest value is selected. But if you don’t want to bother, you can take the average performance of the ventilation system:
- For an apartment or a separate room, you can take a value from 100 to 500 m3/hour.
- For private houses and cottages, it is desirable to take a performance equal to 50-2000 m3/hour.
- For offices this value should vary between 1000-10000 m3/hour.
When you calculate this parameter, you can proceed with the installation of air ducts. Plastic or metal - it's up to you. It depends on the possibilities and requirements for ventilation ducts.
Installation of circular ducts
In total, there are several options for fastening the air ducts of the round ventilation system. Please note that the installation methods for round ducts are slightly different from the installation of rectangular ones. And all these methods can be implemented in the construction and modernization of buildings.
It is necessary to highlight three main ways:
- Nipple or sleeve is the most common type of arrangement of ventilation spans. Sealing of these channels can also be done using such methods. The bottom line is that it is necessary to connect two separate segments of one duct using a third additional element. Moreover, this part can be mounted both outside and installed inside. It all depends on the specific situation.
- Flange is also one of the popular methods of connecting duct structural elements. If you look at the design features of the flanges, you can see that these are small rims, with the help of which the ventilation elements are connected. Moreover, fixation can be carried out using screws, spring mechanisms. The second option makes installation much easier, and the degree of sealing is quite high. Additional details are not required. But there are also mandatory conditions - there must be flanging on the duct components. Without this, you are unlikely to be able to install air ducts for exhaust hoods in the kitchen. All work is not much different from installing ventilation in officepremises. Unless the scale is much smaller.
- The type of connection called bandage is the least commonly used. In this case, a device is put on over the air duct at the flanged ends. This method of installation is very cheap and easy to perform, it is able to guarantee a high degree of sealing. But the production of a bandage itself is a process that is not only laborious, but also expensive. It was because of the high cost of production that the bandage was not widely used.
With the help of such methods it is possible to fix round ducts. Which one to choose is up to you. When installing the air duct in the kitchen, be sure to consider all the features of the furniture and the room. The main thing is that the appearance does not suffer. Pipes should not be conspicuous, they must be hidden.
How to fix rectangular ducts
And now about how you can install plastic air ducts or metal rectangular sections.
Usually used for sealing:
- Flanges. This is the most common type of mount. Just as with round ducts, fixing the flange is extremely important. Otherwise, there will be a slight subsidence of one of the sides or insufficient tightness of the connection. Either rivets or spot welding are used to fix the flanges.
- Tires. This connection part is similar to a flange. But she has an additional tightening lock and a gasket made from porous tape,polymer or rubber band, foam rubber. Be sure to treat all corners and gaps with sealants. And the sealant must be chosen, taking into account the aggressiveness of the external and internal environment.
Please note that it is necessary to immediately distinguish two methods of fastening for metal air ducts - by welding or by folds. And the installation of galvanized steel air ducts can be carried out using such methods. True, welding galvanizing is a difficult task, the use of folds will be much more effective.
