How to make a hood in a private house: technical requirements and an overview of installation rules

Plastic windows, armored doors, on the one hand, keep the desired temperature in the rooms, and on the other - cause problems with air exchange. A properly designed hood in a private house will relieve the feeling of musty and the formation of condensate. In most cases, this is the only way to create a healthy microclimate in it.

We suggest that you familiarize yourself with the options for exhaust devices that can improve the microclimate. Together with you, we analyze the production of calculations using a specific example. We have described in detail the process of installing a forced type of hood for those who wish to do the installation themselves.

The information provided is based on regulatory requirements. The information is supplemented by illustrations, step-by-step photo guides, diagrams, tables and videos.

Options for extracting in a private house

Both in public buildings and in private homes, different types of ventilation systems are used. They differ in purpose, in the way of activating the air flow and advancing the air masses. Ventilation systemdesigned to supply clean air to the house is called a supply air.

The design, the function of which is to remove the exhaust air outside the premises, is called exhaust. A special mission is performed by ventilation with recirculation. In this case, a part of the air discharged from the room is mixed with external cold air masses with further heating of this mixture to the set temperature and its return to the room.

All points regarding the installation of the ventilation system should be considered even at the stage of preparation for the construction of your own home (+)

The movement of air occurs as a result of processes occurring naturally due to the displacement by cold air, which has a greater volumetric weight, of heated air with a lighter weight from the room.

The flow in such a system moves at a low speed, since the weight of the warm and cold mass differs by a small amount. Air duct ventilation with a natural motivation is irrational to use if its horizontal length exceeds 8 m.

More effective is a system with artificial activation of air flow, provided by the fans. Air ducts in this case are long and can pass through several rooms. Elements of the system are most often placed in the attic. This option is justified for buildings of large area.

There is a division into channel and non-channel systems. In the first case, the air moves through the channels and ducts, in the second - there is no organized movement of air. In this case, window transoms, doors have to be opened. Natural ventilation creates more comfortable conditions for the residents of the house.

Necessary preliminary calculations

The initial parameter in the calculation is the volume of air discharged and supplied to the room. There is not one technique, but in the most used, sanitary standards and the area of ​​the room are taken as a basis.

According to the requirement of the first, it is necessary to build on the fact that the need for air in m³/ h for one person spending most of the time in the house, depends on the purpose of the room:

• living room - 40;
• bedroom - 20;
• kitchen - 60;
• Bathroom - 25.

Based on the second criterion, we proceed from the following regulatory requirement: 3 m² per 1 m² of living space³ replaced air. At air duct cross section are guided by the fact that the optimal value of air velocity in the central channel is 5 m / s, and in the side channel - a maximum of 3 m / s.

You can independently determine the diameter of the pipe by the formula:

S = L / 3600 / v,

where L is the performance measured in m³/ h, v - air speed in m / s.

Data on air consumption depending on the cross section of the duct are summarized in the table.

The aerodynamic resistance of the duct with a cross section in the form of a circle is less than with a square. The square shape is more compact, fits organically into the interior of the room, has a large size range

Air ducts are made of metal, plastic, aluminum foil, polyester.The last two relate to flexible systems. Their noise and heat insulation characteristics are good and they are the best suited for a private house.

Natural air exchange in the house

Natural air exchange is based on the property of gaseous and part of liquid substances with a higher temperature rising up. Thus, the exhaust air is naturally removed from the room through a vertically located exhaust channel, while simultaneously tightening the outside air through the supply ducts.

Natural ventilation does not always provide comfort in the home. Often a mixed version is used, when in addition to the natural movement of air, fans are also used (+)

Excessive ventilation is indicated by excess moisture in the room during cold weather or increased dryness in the warm. The presence of a large amount of dust, a lack of oxygen - these are also signs of insufficient airflow from outside.

The consequence of poor drawing is fungus formation under the wallpaper, in the bathroom, soot settling on the kitchen walls, foggy windows.

Checking the operation of the hood is easy. It is enough to bring a sheet of paper to the ventilation grid. With good traction, it will bend towards the ventilation duct, otherwise nothing will happen. It should be concluded that the hood is clogged with something and the channel must be cleaned to ensure traction.

To provide a private house with good ventilation, you need to start with the calculation of air exchange. According to its results, the cross-section of the channels, the type of ventilation system are selected and a sketchy version of the ventilation scheme is made, where the places of passage of the air ducts and the installation of ventilation equipment, the points of intake and output of the air mass are indicated.

Private houses are mainly located outside the city, where the air, unlike the city, is cleaner and there is no need for additional cleaning. Therefore, natural ventilation for a private house is preferable.

A big obstacle to the intake of fresh air is the plastic windows, in which there are no gaps, and the glass is very tight to the frames.

Exit in the supply air valve installation. It is placed on the upper frame, so the air coming from the street goes under the ceiling and only after mixing with conventional flows and acquiring room temperature it goes down.

The location of the elements of the exhaust system should ensure the passage of air flow covering the entire house in the direction from the "clean" premises to those where the air is most susceptible to pollution.

According to this rule, in rooms with special conditions, which include boiler rooms, kitchens with a gas stove, cellars, rooms with fireplaces and columns, toilets, the presence of a hood is mandatory. Valves are also needed in these rooms.

The design features of the supply valve allow you to ventilate the room without creating drafts and without reducing the operational characteristics of the window. No condensation is formed. The slotted valve, as in the photo, can be installed on an existing window unit

Exist vent valvesmounted on the wall. This pipe with a circular cross section is inserted into the through hole in the wall and closed with grilles both from the inside and from the outside.

As a rule, a wall supply fan can supply 50-100 mᶾ of air per hour to the house. Based on this norm and performing the appropriate calculation, select their optimal number

The grill inside can be adjusted - open and close completely or partially. When installing, they prefer the place near the window. Sometimes the supply valve is mounted behind the radiator and then the incoming air is immediately heated.

Private house ventilation requirements

Sanitary standards put forward a number of requirements for aircraft. When deciding how to make an efficient hood in a private house, all points must be taken into account:

1. The inner walls of the channels should be smooth. To ensure this condition, round or rectangular ducts of constant cross-section are inserted into them.
2. The ventilation riser at the bottom is equipped with an inspection door. It should close tightly.
3. An exhaust duct is led to the roof with a minimum of 1.5 m above it. If the roof has a broken shape, then in order to avoid the occurrence of reverse thrust caused by swirling flows, a deflector is installed in the exhaust channel.
4. The ventilation shaft device. If no ventilation system was originally provided for in the building, an attached shaft is attached to one of the walls. To improve traction, it must be insulated.
5. Compliance with the rules of ventilation. It is impossible to combine the mechanical hood of the kitchen with the general aircraft. A separate channel is arranged for her, otherwise there will be problems with the functioning of natural traction in other rooms of the house.
6. The maximum permissible distance from the ceiling to the top of the ventilation grilles is 150 mm. As this distance increases, air stagnation zones will occur.

Doors separating adjacent rooms, even when closed, should not impede the flow of air.

The best solution is to purchase a door with a special decorative grille at the bottom. If a solid door is installed, a gap of at least 2 cm is left between the floor and the door leaf or a series of holes are drilled below.

The essence of the basic requirement is that the volume of air to be removed must be equal to the amount of incoming. If this rule is not observed, then various unpleasant odors will penetrate into the room with air. With a large imbalance between the volume of incoming air and the hood, drafts will appear.

Union ventilation with recirculation

Recirculation is called CB, when the air removed from the room is returned back through the influx with an admixture of fresh air. The disadvantage is that its use is limited by SNiP, and in regions with a cold climate it does not work very effectively. Its action is limited to one room.

Recirculation saves on energy consumption because the power is only used to heat a small amount of air taken from the street.

The circuit of the recirculation system can be turned into an ordinary supply and exhaust ventilation by closing the recirculation valve and completely opening the supply and exhaust. If you do the opposite, the system begins to drive air in a circle.

When the supply and exhaust valves are only partially opened, mixing of fresh outdoor air will begin. By adjusting the degree of opening, optimize the flow of elements that provide a comfortable life.

Installation of forced extraction of a private house

Forced air exchange in comparison with natural wins in many respects:

1. It works regardless of the weather.
2. It cleans the air more effectively.
3. It is possible to adjust the rotation speed and fan power.
4. The air flow can be set in motion not only with a duct fan, but also through the use of monoblocks, which are easy to install.

The main disadvantages are the dependence on power supply and the need for periodic replacement of individual elements. There are several mechanisms for forced ventilation.

It can be a single supply and exhaust installation, a typeset and supply system, exhaust, duct air conditioning. The most efficient is considered to be supply and exhaust fan. The design includes a fan, automation, sensors, filters.

The distribution of cold air in the room during the operation of the supply and exhaust ventilation is prevented by a special damper located in the housing

Forced hood as standard has a single fan and is designed for small rooms. In NE type-setting equipment is the same, but it is placed separately. System power is in the range of 80-7,000 m³/ h

From the practical recommendations of experienced craftsmen it follows that in a small house consisting of 2 rooms, an extract hood that processes from 200 to 300 m works effectively³ air per hour.

In buildings of large area, it is necessary to mount hoods with a capacity of 350 to 500 m³/ h

Kitchen hood mounting technology

The hood in the kitchen is usually placed above the stove. It is necessary that the exhaust umbrella protrudes beyond the plate by 100-150 mm.

Productivity is selected with an orientation to the parameters of the premises using the formula:

P = S x H x 12

Where the first symbol indicates the power of the second - the third area - the height of the kitchen.

Depending on the installation method, kitchen hoods are hanging, wall, island, built-in, and according to the type of functioning, circulation and supply

Air ducts usually go along an indirect path, due to which the exhaust power may decrease. To guarantee, 30% is added to the value obtained as a result of the calculation. The installation technology is simple therefore, having understood the scheme, you can do all the work yourself.

When there is no built-in aircraft. then first make a hole in the wall, matching in diameter with the cross section of the exhaust pipe. If you neglect this recommendation, the operation will be accompanied by increased noise, and air will exit at a lower speed.

The structure itself is located at a distance of at least 0.7 m from the surface of the electric stove and 0.8 m from the gas.

The next step is the marking of the mount. Sometimes a template is included in the hood kit, but if it doesn’t turn out, you can use the level and tape measure. Next, fix the exhaust umbrella, observing the horizontal.

Connect the structure to a previously made outlet, connect to the mains and test. If the house has a geyser, then the ventilation pipe can be led into the chimney of the boiler or heating furnace.

The process of installing a cooker hood with a masking dome will be demonstrated by the following photo selection:

Forced bathroom exhaust hood of a private house

In the bathroom for forced ventilation, the installation of exhaust fans operating in a humid environment is performed:

1. bring power to the room and install the outlet;
2. a hole is made in the wall corresponding to the section of the fan clutch;
3. the sleeve is placed in the hole;
4. drill mounting holes;
5. connect the cable;
6. removing the front panel from the fan, fasten the latter to the wall;
7. return the removed panel to its place;
8. outside fasten a lattice.

It is advisable to use such a system in a bathroom located on the second floor. Typically, the CB of this room with the mandatory presence of a ventilation shaft is laid in the project. The air flow through the gap between the floor and the door, as well as through the window.

To create forced ventilation in the bathroom, a fan is built into the air exchange system. It draws exhaust air from the room, opening the way for a new portion of air from neighboring rooms

Sometimes, as an option to resolve the issue of how to make an outlet in the combined bathroom of a private house, something similar to a drainpipe with a recommended diameter of 110 mm protruding above the roof level is carried out along the wall of the building.

In device ventilation of hygienic premises axial fans are used, the installation of which is performed in the standard sequence:

Basement ventilation device

For basement simple and effective ventilation is needed, otherwise it will not meet the demands of it. For installation, 2 pipes with a section from 80 to 150 mm, thermal insulation, protective visors, grilles are needed.

The supply pipe is mounted at one end into the wall, retreating from the floor for about 0.3 m. The top of the pipe with a length of approximately 5.5 m should run along the outer wall. The draft is ensured by the temperature difference in the upper and lower parts of the pipe.

Large-sized basement ventilation can only be handled by the supply and exhaust version of the ventilation system.Vertical ducts are placed in the corners, an exhaust pipe is installed under the ceiling, and a supply pipe is installed at a certain height above the floor surface

The top of the pipes is protected by visors, which, in addition to the protective function, play an important role in regulating the speed of air passage.

The draft intensity also depends on the difference in the lengths of the supply and exhaust pipes. The larger this difference, the more powerful the flow. Normal ventilation should provide a 2-fold air change within 60 minutes.

Conclusions and useful video on the topic

Video # 1. How to implement a ventilation project in accordance with all the rules:

Video # 2. Familiarization with the work of natural ventilation:

Numerous factors influence the ventilation efficiency of your own home. When choosing the type of aircraft and performing calculations, you need to consider everything. Only when this condition is met will it function flawlessly.

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