Is a fan riser necessary in a private house? Fan riser: purpose and its alternative. What diameter should the fan outlet be?

Not everyone knows why the sewer system needs access to the roof. In fact, the fan riser is an important part of this system and if insufficient attention is paid to its installation, the result can be unpleasant. The article examines in detail what a sewer riser in a private house without access to the roof or through the roof (which is done more often) is and what it is needed for. Having understood this issue, you can choose the highest quality and most reliable option for installation.

What it is

When a private house is built, it is necessary to connect various communications to it. One of them is sewerage. At first glance, you might think that it is enough to equip it with only a sewer drain. In fact, this is not enough.

In order to explain the purpose of the vent riser, you need to remember how the toilet flushes in more detail. After the sewage is drained, a certain amount of water then gets there. Some of it remains in the toilet. It is actually a water seal, the role of which, in particular, is to prevent the unpleasant odor from the drains from entering the living quarters. It is important to understand that this protective layer of water is located inside the toilet.

If several such plumbing fixtures are installed in the house, then each of them, which is not currently in use, has such a water seal.

When one of the toilets is flushed, the pressure drops for a short period of time immediately after the sewage and drained water flows out. Since all the others are connected to this pipe, their water seals are broken and an unpleasant odor penetrates into the premises.

It is important to note that this situation exists not only in relation to toilets, but to all drains that are connected to the sewer system. For example, we can talk about a water seal in a bathroom or in a sink, if they are connected in the specified way.

This situation could have been avoided if the pipe had an additional outlet through which air could freely flow into it. In this case, low pressure would not arise at the drainage point and the water seals would not be broken anywhere.

Odors from the sewer could also escape through such a pipe. A sewer riser is a pipe that performs the specified functions, which is connected to the sewer system of the house and led outside it.

How necessary is it? In fact, the system in question is actively used in apartment buildings. In the sewer system, drainage from apartments occurs in a vertical pipe.

Its lower end is connected to the drainage system, and the upper end is brought out onto the roof and actually serves as a drain riser.

Technical requirements

The outlet pipe does not have any specific diameter requirements. Typically, a pipe similar to a sewer pipe is used for this purpose in apartment buildings.

Let’s assume that in a private house, a pipe with a diameter of 5 cm is used for drainage from the sink, the opening of the flush tank is 7 cm, and the pipe from the toilet is 10 cm. In this case, a drain pipe on the roof with a diameter of 10 cm can be used for the drain riser.

Practice confirms that such a pipe is sufficient to ensure constant pressure in the drainage system and to provide ventilation in it. If we are talking about a one-story private house in which only one toilet is installed, then here you can do without installing a vent riser.

This is due to the fact that the drain in this case will not be able to create a strong enough decrease in pressure so that unpleasant consequences can be felt.

However, in some cases, roof risers are necessary:

If the house has at least two apartments with fully equipped sewerage systems, provided that they connected to a common net.

A sewer outlet to the roof for ventilation of the riser is required in a house where there is more than two floors.

If equipped horizontal sewer distribution provided you connect to it three or more number of plumbing fixtures.

It is also necessary to provide:

Although usually boners sewers have diameter 10 cm, however, sometimes there are situations when this is used pipe diameter 5 cm. Then the outlet of the vent pipe to the roof is compulsory.

If the house has pool, dumping water into sewer system, the use of the design in question is also necessary. This is due to the fact that in such a situation it is possible to reset large quantity water.

A fan riser and access to the roof are needed in cases where drain happens in private septic tanks located Near home.

If the house one-story, But bathroom And toilet located at different levels, and the drainage occurs in one pipe.

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Carrying out installation

When installing a riser, it is important to pay attention to some points:

No need underestimate diameter outlet pipe. If it is too narrow, then its thickness may not be enough for quality work. Pipe diameter 100 mm is most suitable for this purpose.

Horizontal part of the sewer system should not be located on same level. In this case, there is a risk of formation water or air traffic jams It is recommended that the pipe be installed with weak slope. It is usually considered sufficient to use a slope of two centimeters per meter of length for this purpose.

Sometimes when installing a system they do riser outlet not on the roof, but on attic. Do this categorically Not recommended. From exposure to escaping air, the layer thermal insulation the roof may become saturated with moisture. Another consequence could be decay rafters

When installing a pipe on the roof, it is sometimes installed on its hole deflector. It will protect from hits precipitation and random debris. Additionally, its influence in windy weather will be expressed in increasing traction. But there is another opinion. It is believed that this or another additional device installed above the pipe opening contributes to the formation of condensate, which in frosty winter weather will lead to icing pipes from the inside. As a result, it will be partially clogged and may cease to perform its functions.

When carrying out installation, you need to consider:

Fan riser pipe is not recommended move away from vertical sewer drain. If for some reason this is difficult to do, then transitional It is better to make the connection using corrugated pipes

It is believed that height pipes above the roof should be 50 cm. It is recommended that the roof outlet be located on distance no less 4 meters from balconies or windows.

System reliability will be higher if you install back valve. It settles in where it happens drain into the public sewer pipe. Its action is that drains pass from an apartment or house to the outside free, and in reverse direction gases And liquids don't penetrate at all.

Video description

A video with a detailed description of what a drain pipe is, how it works, how to make it, how to prevent sewer odors and avoid mistakes:

On our website you can find contacts of construction companies that own , provide . You can communicate directly with representatives by visiting the “Low-Rise Country” exhibition of houses.

Is it necessary to put it on the roof?

Sometimes in apartment buildings, residents of the upper floor themselves dismantle the riser pipe leading upward.

The motivation for this decision is insufficient knowledge of the principles of sewerage operation and the idea of ​​a drain riser as something superfluous and unnecessary. Soon after this, a persistent smell from the sewer pipe appears on the upper floors.

The situation can be improved. In this case, there is no need to install vent pipes on the roof. It is enough to attach a special valve to it. It will not release air outside, but when a low pressure zone forms, it will let air in, which will prevent the water seals from breaking.

There is no need to put such a riser on the roof. The valve must be installed at the top of the sewer pipe system. Although this is convenient (there is no need to install a pipe passing through the roof), such a device is not highly reliable.

Vacuum valve for installation at the top of sewer pipes Source drive2.ru

To install a fan riser, you should pay attention to the following:

When bringing the pipe to the roof you need cover the hole with a grill. This is necessary to protect against birds.

Sometimes when this system is running it sounds quiet unpleasant noise. In order to get rid of it, you will need wrap pipe soundproofing coating.

It's not always possible withdraw roof drain pipe from each sewer system. In this case you can provide one pipe per several risers.

Installation of a fan riser

Plastic or cast iron pipes can be used for this. There are several options for laying them. It can be straight, oblique or with a horizontal section. The first of these options is considered the most effective, but it cannot be implemented in all cases. Less suitable is the location of the fan pipe at an angle.

Options for laying the vent riser, pipe material and outlet openings vary Source sovet-ingenera.com

If it is not possible to carry out the installation using the previous methods, then you will have to use an installation where a horizontal section of the pipe will be used. It is laid within the attic from the point where it will be possible to install a vertical pipe.

The exhaust pipe exits to the roof using one of the following methods:

It can be done in the form pipes on the roof.

Sometimes it is done through sloping wall roofs.

Sometimes it happens that the outlet is located inside the attic premises.

The last option is of lower quality. At the same time, moisture escapes through the pipe, which can lead to condensation and rotting of the roof. In addition, sewer odors spread through the pipe. When it is located on the roof, this impact is minimized.

The second option is considered vulnerable to icing.

In the attic, you can equip an exit from the riser only if you install a special valve there, which can only let air in, but not out.

Video description

For a story about a vent riser for ventilating a septic tank, see the following video:

Conclusion

The use of vent risers is mandatory, except in a one-story private house for one family. If this is not taken care of, unpleasant odors will constantly appear in the apartment. A correctly selected system for installing a fan riser will completely solve this problem.

The construction of any private house is not complete without the installation of utilities. In particular, we are talking about the sewer system. When installing it, you must not forget about installation of a fan riser. Next, let's look at what it is and why this device is needed. The article will also provide brief instructions for installing the riser, recommendations from experts, regulatory requirements, and also describe an alternative option and the most common errors in operation.

Purpose

Fan riser in a private house- part of the pipe extending from the central sewer riser. It goes outside the building and removes unpleasant odors from the house. The absence of this element leads to a breakdown of the water seal. As a result, an unpleasant odor appears in the room. Sewer cleaning in such cases it will not help to get rid of it.

Each plumbing fixture is equipped with a discharge pipe with an elbow. There is water in the bend, which acts as a water seal. It prevents the penetration of unpleasant odors into the room. When the drain is released, a vacuum occurs. The skull receives air from the street, which ensures normalization of pressure. Due to this, odors do not penetrate into the room.

Always do you need a fan riser?? You can do without this device in small buildings with one bathroom. If the house has 2 toilets or 2 bathrooms, it is necessary.

Important Factors

A fan riser is equipped if:

• The building is two floors, and there is a bathroom on each floor.
• The diameter of the sewer drain is 50 mm.
• There is a swimming pool or other facility in the adjacent area that requires regular discharge of large volumes of water.
• The house has a sealed sewer system with a septic tank.

Development of an installation plan

To mount correctly sewer pipe, it is necessary to take into account the following factors at the design stage:

• The pipe should go to the side in which the vapors are diverted due to air flows.
• The pipe is removed to If this is not possible, installation is carried out through the wall.

Elements

Ventilation sewer riser includes:

• Pipes.
• Ventilation ducts.
• Fitting.
• Connecting elements.

Installation principles

How to properly install a fan riser for a home? It is worth saying right away that installation planning must be carried out simultaneously with the design of the internal sewage system. To increase the efficiency of the riser, it is necessary to avoid a large number of corners and bends.

Ideal position fan pipe for sewerage is strictly vertical. It is discharged through the interfloor ceilings into the attic and then onto the roof. But in practice, unfortunately, it is not always possible to implement such a project.

Usually in private houses additional connecting elements are used. For example, an auxiliary pipe can be connected to the main sewer riser, a separate pipe can be installed at the same distance from the sewer risers, etc.

The key task at the system design stage is the correct calculation of the diameter of the pipe for the outlet. It cannot be larger than the size of the sewer pipe (110 mm). Ideally, the diameter should correspond to the size of both the central riser and the pipe connecting the internal and external parts of the system.

When designing, special attention should be paid to the location of the riser. It should not be located near air conditioning equipment, as well as the removal of combustion products from a heating boiler.

Installation of a fan riser does not present any particular difficulties. However, some nuances should be taken into account.

For central sewerage, it is advisable to use a 110 mm pipe. The ventilation riser should have the same diameter. Typically plastic pipes are used. If the system consists of elements made of different materials (for example, the riser is plastic, and the sewer is cast iron), rubber adapters should be used.

To connect several risers, angles of 45 or 135 degrees are used. Areas located horizontally should be laid with a slight slope (0.02%) towards the drain outlet. If you need to change the angle, use a special bend with a rotation of 135 degrees.

Replacing the fixture

The need to replace the fan riser or a separate part of it may be due to various reasons. For example, some owners, during a major renovation, update all engineering systems in the house.

Replacing the riser is carried out on the same principle as sewer repair. In this case, a number of conditions must be met:

• When working indoors, you should organize
• Replacement of elements is carried out using a respirator and gloves (rubber).
• Upon completion of work, it is necessary to check the tightness of the connections.

If necessary, simultaneously with replacing the riser, you can also sewer cleaning.

Regulatory Requirements

There are several indicators that should be taken into account when installing a fan riser:

• When leading part of the pipe to the roof, the distance to the roof must be at least 30 cm.
• If the house has an attic (attic), the length of the riser is at least 3 m.
• A distance of 4 m should be maintained between the pipe and the loggia or window opening.
• The fan riser must be installed in a heated room. If this is difficult, the pipe must be insulated.
• The riser cannot be discharged through the chimney.
• Protective elements from birds, insects and precipitation are mounted on the outside of the upper part of the pipe.

Common Mistakes

Despite the relative simplicity of installing a fan system, there are a number of rules, violation of which can lead to negative consequences.

For example, some owners of private houses cut the pipe in the attic. As a result, unpleasant odors begin to fill it (or the attic) and subsequently penetrate into the house. Accordingly, the design of the system loses all meaning.

Another mistake is installing the pipe along the outer wall. In this case, there is a high probability of condensation formation.

Some home owners install an additional device - a roof aerator. It provides improved traction. Meanwhile, installation of this element is not always advisable. As a rule, the outflow of sewer evaporation slows down. As a result, again, unpleasant odors begin to penetrate into the premises.

Alternative option

It is a vacuum one. It is mounted at the end of the riser directly in the house.

The valve is a small device made in the form of an end cap. Under a certain pressure, it allows air into the sewer, but does not release it back. At first glance, this is a fairly effective solution to the problem. However, there are several important nuances.

The diameter of the holes that let air in is actually several times smaller than the size of the riser. Doubts immediately arise about the effectiveness of the device. As practice shows, in an apartment building with a fairly high load on the sewer system, one such device is not enough - at least several are needed. Accordingly, it is necessary to allocate enough space to install at least 4-5 valves.

Another problem lies in the design of the device. The valve will be effective if the gasket inside it is positioned strictly horizontally. Even with a slight misalignment, the valve will jam in some position (closed or open). In any case, this will lead to unpleasant consequences.

Valve operating principle

Inside the device there is a special spring with little resistance. Tightness is ensured by a rubber sealing gasket. The operating principle of the vacuum valve is as follows:

• The sewage drains pass through the riser and provide a vacuum in the system.
• The valve shutter opens.
• Air is sucked from the siphon and passes into the sewer network. Due to this, the vacuum is extinguished.
• After the pressure has stabilized, the spring mechanism begins to operate. Due to this, the shutter is closed and air does not enter the room.

What should you pay attention to?

It should be said that installation cannot be called a full-fledged alternative to a fan riser. The fact is that the device gets clogged quite quickly. When the siphon dries out, the efficiency of eliminating gases is significantly reduced.

If it is not possible to install a check valve on the riser, it can be mounted on another horizontal part of the pipe approaching the riser.

SNiP

The problem of unpleasant odors in the room arises not only in the absence of a vent riser. The quality of plumbing equipment is also of great importance. When choosing it, it is necessary to check the presence of a hydraulic seal. Modern equipment in most cases is equipped with this device. However, there are models without it.

In addition, the Russian Federation has a special regulatory document SNiP. It lists the factors in the presence of which the installation of fan risers is mandatory.

Consequences of missing or incorrect installation

In simple terms, a fan riser is ventilation. Its key task is to ensure air flow into the sewer system. This, in turn, ensures the ability of the drain to quickly cope with the movement of volume and eliminate unpleasant odors.

In apartment buildings it is impossible to do without a vent riser. Housing and communal services employees have a very negative attitude towards any work affecting this part of the sewer system, even if the owner of the living space wants to install a vacuum valve instead of a pipe. Above we have already discussed the disadvantages of such a device. You shouldn’t insist on your own and redo the system. Otherwise, serious problems will arise. They will ruin the lives of all the neighbors whose apartments are located along this riser. The unpleasant odor will spread very quickly.

Situations are especially dangerous when a plug is placed on the fan riser. In this case, the unpleasant smell will definitely go into the apartments, since there is nowhere else for it to escape. It will penetrate into the premises through pipes and parts of pipes suitable for plumbing equipment and sinks.

Often the situation is aggravated by the fact that flushing the toilet results in the release of a large volume of water into the system. It acts like a piston and draws out air behind it. As a result, the pressure is disrupted. To stabilize it, the suction of water seals from the siphons of sinks, bathtubs, and kitchen sinks begins. In the absence of water in the knees, unpleasant odors easily penetrate into the premises.

Another problem is clogging of the sewer network. Frequent pollution results from the lack of adequate air flow. The system will no longer cope with its functions, and the owner of the premises will have to clean the sewer very often.

The owner of a private house, of course, does not experience the same restrictions that burden residents of apartment buildings. He can choose whether to install a drain pipe or not, or whether to use vacuum valves instead. However, not all owners of private houses have the necessary skills and have the necessary tools at their disposal.

To prevent potential problems, it is advisable to entrust the installation of the riser, or better yet the entire sewer system, to professionals. Specialists will develop a project taking into account the wishes of the customer and the features of the structure. In addition, they will select the most suitable materials for installing the system.

Of course, you can do the installation yourself. In this case, it is advisable to first consult with friends who have already installed the system. If plastic elements are used, then one person can handle the installation. The weight of pipes, even long ones, is quite small. To install cast iron elements you will have to use someone's help. In this case, the installation can be carried out by two people.

Conclusion

The sewerage system is considered one of the main engineering networks in the house. Its efficient operation ensures comfortable living regardless of the time of year.

It should be said that the systems can be implemented using not only plastic, but also cast iron pipes. They are used, as a rule, in areas with harsh climatic conditions. In regions with a milder climate, it is more advisable to use plastic pipes. If necessary, they can be insulated with any suitable material. Construction stores offer a wide range of different insulation materials. The most common material for protecting pipes is mineral wool. When using insulation, it is important to provide protection from getting wet.

When installing a vent riser, it is important to comply with the standards established by SNiP. A pipe next to a window will not look very aesthetically pleasing. In addition, the further it is located from the opening, the less likely it is that odors will penetrate into the room.

After installing the riser, it is necessary to periodically check its condition. As practice shows, plastic pipes last quite a long time, but there is always the possibility of clogging. The check can be done quite quickly. The entire system is collapsible, you can easily separate the elements.

The sewage system must be connected to the ventilation system. This is necessary to maintain constant pressure in the drainage system and ensure removal of unpleasant odors. A fan riser in a private house is used precisely for such purposes.

Why is it needed?

To prevent sewer odors from entering the living room, siphons are used in toilets and sinks. After draining the water, a certain amount of liquid remains in them. The level of this water depends on the pressure in the drainage system. But, if at one moment a vacuum forms in the vertical riser, then the water will leave the siphons. Because of this, the operation of the system will be disrupted.

This can happen if the throughput of the siphon is equal to the amount of one-time drainage. For example, with a toilet outlet diameter of 110 mm and a washbasin outlet of 50 mm, a 150 mm siphon is used. Then, when flushing the toilet and sink, the siphon will completely close.

If the house is one-story, then installing a vent riser is not necessary, but in a private two-story building it is necessary. How to determine whether a drain is needed in a two-story house:

1. The house has a swimming pool;
2. The plot is small and there is a drainage well or storage tank in close proximity to the house;
3. The main riser has a small cross-section, smaller than that of some consumers (say, a toilet).

Rules for installing a drain pipe

There are certain SNiP requirements for installing a vent riser in a country private house. The most important rule is that the diameter of the main sewer pipe (main riser) must exactly match the size of the ventilation communication. This is extremely important, otherwise fecal waste may enter the ventilation outlet from the sewer drain.

There are several types of fan pipe:

1. Vertical;
2. Horizontal;
3. Angular.

Depending on the requirements for the sewer outlet and the type of sewer system, a scheme for its installation and wiring is selected. Therefore, fan pipes can be of any design.

The slope of the drain pipe is also very important. The minimum figure is 30 mm for each linear meter of riser, with a diameter of 50 mm. It turns out that if the total length of the waste pipe is 3 meters, then the optimal slope will be:

3000 / 30 = 100 mm. Of course, this indicator is standardized, but experts start from this standard. The slope for a 110 mm pipe is calculated in the same way - 20 mm is used. Another key rule is that the larger the drainage cross-section, the smaller the slope. The maximum permissible diameter for a fan riser is 200 mm, and its slope should be no more than 7 mm.

Also, in addition to the communication itself, you need to install a fan - it will pump air, and a non-return air valve. An aerator or valve is a device that prevents the penetration of fecal matter into the pipes of toilets and sinks. It consists of a membrane, a lid and a locking device. When the mass pressure in the main riser reaches its maximum, the membrane, under the influence of pressure and the locking mechanism, changes its position. The waste flows through the valve and into the sewer. They cannot return back, because the diameter of the cover exceeds the cross-section of the pipe.

And the last requirement is that it is very important that the ventilation outlet from the sewer is discharged directly into the atmosphere. Then the odors of the wastewater will quickly and easily dissipate. To ensure quick “refreshing” and constant pressure, the end should be in a cold place - unheated, and the beginning of the communication should be indoors.

Installation

Before starting work, a plan is developed. The level of the ventilation riser must be higher than the consumer outlets in the sewer system. In addition, the location of the valve and the slope of the bends are calculated separately.

Let's look at how to do it yourself:

Video: Features of installing a fan riser.

Periodically, the ventilation fan outlet will have to be cleaned. To do this, you can call specialists, or do all the work yourself. To clean, you will need a flexible rubber brush or a regular plumbing cable with a brush at the end. This procedure must be carried out every year.

Price overview

You can buy a drain pipe for a private home at any plumbing store. Manufacturers offer bends made of PVC and steel. Depending on the material from which the outlet is made and its diameter, the price of this communication varies significantly. In addition, it can be socket or fitting (installation of the latter requires the installation of an additional fitting).

When independently installing a sewer system in an individual home, not all owners have a good idea of ​​how to install it correctly. The sewer system is an integral part of modern homes. One of the required elements of such a system for its proper functioning is a sewer pipe. Many owners of private households do not fully understand its purpose and proper use when installing a sewer system.

What it is

A drain pipe is a part of the sewer system pipeline that connects it directly to the atmosphere and eliminates the emptying of water seals of plumbing fixtures from possible vacuum when draining waste water.

In turn, a water seal is a specially curved sewer pipe at the outlet of a plumbing fixture. It is naturally partially filled with water, which acts as a water plug to prevent unpleasant air from entering the sewer pipes directly into the room. For example: the water seal of the toilet is made in the housing, and a special product is screwed to the sink - a siphon.

Important! If there is no drainage pipeline in the sewerage system, then at the moment of draining a certain amount of water, water plugs may disappear at nearby water seals and then not very pleasant sewer odors will freely seep into the living quarters through the empty pipes.

The drain pipe is also called the ventilation of the sewer system. Its presence in the sewer allows you to solve two important problems simultaneously:

• Ventilation removes harmful gases from the sewer system;
• Pipeline ventilation maintains atmospheric pressure in all elements of the sewer system, preventing air rarefaction from occurring when large volumes of water are drained simultaneously.

Hence the conclusion: the drain pipe is an important attribute when installing a sewerage system in residential buildings.

Device

The presence of drain risers in the sewer system of multi-apartment residential buildings is mandatory and is regulated by current government documents and building regulations. As a rule, sewer ventilation risers are made straight, due to the fact that the processes occurring there are gravity, not forced, and it is necessary to minimize the number of outlets and various narrowings for the most free passage of air flows.

Sewage systems in individual houses do not have such volumes of wastewater as in multi-apartment residential buildings, therefore the requirements for the installation of drain risers are less complex and allow for significant deviations for the sake of practicality and minimizing construction costs.

The sewer pipe is basically the upper continuation of the sewer riser, so it must end at the roof of the building. A standard deflector must be mounted at the end of the pipe, so that the distance from the surface of the roof ridge is 30 centimeters higher. It is not recommended to install sewer ventilation on the façade of the building.

Important! You cannot install the outlet of the sewer riser in the attic of the building or near windows and near balconies.

To install a fan riser, you can use pipelines made of any materials. Thus, plastic, cast iron or steel pipes must meet only one condition - to be corrosion-resistant, since sewer gases will contain many aggressive substances.

Diameter

There are no special requirements for calculating the diameter of sewer pipes; for multi-apartment residential buildings, it should be equal to the diameter of the sewer riser itself. But for individual construction, it is allowed to use pipes with half the diameter compared to the main riser, so only air will pass through the drainage part of the pipeline, and it has several times lower density than the drained water at the bottom of the sewer network.

Basically, when constructing an individual residential building, to calculate a separate sewer line, which includes a sink with a pipe with a diameter of 50 mm, a cistern with a hole of 70 mm, a main pipe from the toilet of 100 mm and a common riser, also of 100 mm, They use a fan pipe with a diameter of only 50 mm. Practice shows that this diameter is quite sufficient to maintain constant pressure and provide constant ventilation of the sewer system.

Is a vent pipe needed in a two-story house?

Guided by building regulations, an exception to the execution scheme is allowed when constructing a sewerage system for a waste pipeline in individual houses. This conclusion is based on the fact that in small households large volumes of drained water cannot be generated simultaneously.

Installing a drain pipe for the sewer network in low-rise construction will not always be superfluous, therefore it is recommended that at the stage of constructing a new building, the sewer system should be installed according to the traditional scheme with all functional elements. Although there are a number of clear criteria under which the installation of a sewage pipeline is a necessary condition for the proper functioning of the sewerage system, namely:

• There are two residential sections in the house, each with its own sewer system, which is combined into a common network;
• The house has more than two floors, equipped with common risers;
• There is a horizontal sewer distribution with three or more plumbing fixtures connected;
• The presence in the house of sewer risers made of pipes with a diameter of 50 mm;
• The presence of a swimming pool or similar structure that allows large simultaneous discharges of water into the sewer system;
• If there are individual sewer septic tanks located on the site directly next to the house.

In any case, when, during a single-stage discharge of water, a situation may arise in which the section of the sewer pipe is completely filled and it becomes possible to create a vacuum in the higher-lying water seals, then the installation of a drain pipe becomes a prerequisite for the proper functioning of the sewer system of the house.

If a residential building is equipped with a small number of plumbing fixtures and mostly with small-diameter sewer pipes, then the use of a drain pipe is not necessary, since it will not have a significant impact on the operation of the entire sewer system, but will only require the expenditure of extra funds.

Advice: For one-story construction, installing fan pipes is not advisable.

How to check

When purchasing an existing country house or cottage, you can easily check and make sure whether a drain pipe is present in the sewer system. So, if you suddenly flush the water from the toilet, it should not disappear from the water seals of the plumbing fixtures located above. But the characteristic appearance of squelching sounds in the siphons of sinks and bathrooms leads to the conclusion that not everything is in order with the sewage system in the house and this can subsequently lead to the appearance of unpleasant odors in the premises.

Installation

The requirements for the installation technology of sewer pipelines are the same as for other sewer pipes. This is how you can list the main installation conditions:

• Sections of pipelines laid horizontally must have a minimum slope of 0.02% towards the sewer stacks;
• Several sewer risers can be combined with one drain pipe;
• The direction of the waste pipeline can be changed after the last water seal and only above the level along the riser;
• When combining three or more pipelines, it is necessary to make a connection with angles of 45 and 135 degrees, respectively;
• When the roof or attic is in use, the fan deflector is installed at a height of 30 cm closer to the roof ridge;
• The exhaust pipe outlet is allowed no closer than four meters horizontally from balconies or skylights.

Important! Any combination of pipelines of waste pipes, ventilation systems and chimneys is strictly prohibited.

Do I need to insulate and soundproof?

It is not at all necessary to insulate sewer pipelines passing through residential premises, as well as sewer pipelines. But in an unheated attic it is worth making at least minimal thermal insulation of the pipes so that during severe frosts the ice does not freeze inside, since water vapor is much lighter than air, and they will tend to rise up the pipe, where they will freeze on the cold walls.

Sound insulation of the drain pipe must be carried out only if it passes openly through residential premises. If this cannot be avoided, then the insulation work is quite simple and is carried out in the same way as for all sewer pipelines with the same ease. The only thing that complicates the process is the variety of acoustic processes in pipes, which directly depend on the materials from which the pipelines are made.

Thus, the sound insulation properties of cast iron pipes are much better than those of their plastic counterparts. This is due primarily to the properties of the granular structure of cast iron and the larger wall thickness, so such pipes, as a rule, do not require additional sound insulation.

Sound processes occurring in plastic pipes can be divided into four main components:

• Impact nature, when falling water and feces repeatedly hit the walls of the riser;
• Atmospheric nature is the penetration of wind and precipitation noise through the outer part of the pipeline;
• Resonant nature from the presence of extraneous noise in the pipes caused by the interaction of the sewer pipeline with the building structures;
• Vibrations that occur when there is contact with any operating equipment.

The main part of the work on sound insulation should be carried out at the design stage of a residential building, so that all sewer risers do not pass through residential premises and are installed exclusively in special boxes or sewer shafts, which themselves are shielding devices and prevent the spread of noise.

If, after all, the vent pipe is located open in a living room, then it can be easily soundproofed by wrapping the pipe with strips of inexpensive polyethylene foam in two or three layers.

Vacuum valve or drain pipe

A vacuum valve is a special device that performs the same main function as a drain pipe, namely, it prevents the appearance of vacuum in the sewer system, thereby eliminating the emptying of water seals of plumbing fixtures and making it impossible for unpleasant odors to come from the sewer.

For individual houses, a vacuum valve is an alternative and a complete replacement for a drain pipe. It is much simpler in design and easily fits into any existing sewer pipeline, while it does not require a complex outlet device and is much cheaper in terms of capital costs when purchasing and installing.

Important! Do not confuse two different types of sewerage valves - a vacuum valve and a check valve. They differ both in design and in the functional purpose they perform in the sewerage system.

The vacuum valve is designed as a fully automatic device, which begins to operate at the slightest vacuum in the sewer pipe when draining water. The sensitive element of the valve is made in the form of a special membrane made of rubber or silicone.

It works due to the difference in pressure inside and outside the pipe, opening when a vacuum occurs when draining water, thereby ensuring the flow of missing air into the sewer network. Under the influence of internal forces, the membrane immediately returns to its place when the pressure is completely equalized, preventing the penetration of air from the sewer pipe.

The only disadvantages of a vacuum valve are:

• Laying (gluing) of the membrane to the installation site (socket) during very long periods of inactivity,
• Deformation of the shape of the membrane over time due to drying out of low-quality rubber or from prolonged and frequent operation.

Both of these disadvantages of the vacuum valve are not so critical and can easily compensate for the inexpensive cost of purchasing a new device and the ease of its reinstallation.

Everyone decides for themselves how to install a sewer network in their home. After all, there is no definite answer to the question: a vacuum valve or a waste pipe, or it is simply not worth complicating the sewerage system with unnecessary elements. Here, this article, common sense, technical calculations and your life experience are your advisors.

Many people undertake to install sewerage in country houses on their own, however, not all of them know what a drain pipe is and why it is needed at all. This, in turn, leads to various problems that arise during the operation of the system, in particular, unpleasant odors appear in the room. Therefore, in this article I will tell you about the purpose of this sewerage element, its installation and some other important nuances.

Purpose of the drain pipe

General information

So, the ventilation section of the sewer is called a fan pipe. In fact, this is a continuation of the riser, which is led out through the attic. Its task is to stabilize the pressure in the sewer system.

But how can it affect unpleasant odors in the room? After all, to avoid them, siphons are used, inside of which siphons are formed.

In fact, everything is very simple - a large volume of wastewater generated, for example, during the process of flushing a toilet, works on the principle of a piston in a pump. Those. Before the drains in the system, the pressure increases, and behind them, on the contrary, it discharges.

As a result of air rarefaction, if there is no ventilation, the water seal breaks down and air leaks through the drain hole of the plumbing fixture, after which an unpleasant odor appears in the room. As a rule, this problem occurs in a plumbing fixture where the water seal is weakest; however, sometimes the water seals fail in several places simultaneously.

The process of water seal failure is accompanied by a characteristic gurgling sound coming from the drain hole of the plumbing fixture.

Linguistic confusion arose among the people, as a result of which the plumbing pipe began to be called the section of wiring between the toilet and the riser, or even the entire sewer system.
This is where the concept of a drain pipe eccentric came from, which means an adapter that allows you to connect the toilet to the sewer.

If there is ventilation, air flows freely into the air, thereby stabilizing the pressure, preventing such problems.

When is ventilation necessary?

Ventilation of the sewer system is, first of all, necessary in houses with two floors (if plumbing fixtures are available on each floor), and even more so in multi-story buildings with a large number of apartments.

In most cases, a drain pipe is not required in a private house, however, below are cases when you cannot do without it:

• if the house has a swimming pool or several bathrooms that can be used simultaneously. It should be noted that the bathrooms in this case also include a washing machine, which discharges water into the sewer during the washing process;
• if the diameter of the riser is 50 mm, in this case even a small volume of drainage can lead to the failure of the water seals;
• if the septic tank is located near the house, in this case the septic tank is also ventilated through a drain pipe, as shown in the diagram above.

To conveniently and quickly connect the washing machine to the sewer, you should install a special siphon with an outlet for the washing machine on the plumbing fixture closest to it.

In addition, ventilation of the riser may be required in some cases when the sewerage system is not properly installed.

Design and installation rules

As mentioned above, the ventilation pipe is a continuation of the riser. It is made from the same sewer pipes. As a rule, its diameter is 110 mm, i.e. diameter is equal to the diameter of the riser.

A “fungus” is placed on top of it, which prevents precipitation and various debris from entering the riser.

It should be noted that for the normal functioning of ventilation, the sewer pipe must be installed according to certain rules:

• the diameter can be equal to the diameter of the riser or be larger, but in no case less;
• on the roof the structure should be located 30-50 cm above the ridge. In cases where the roof is in use, for example, if there is a terrace on it, the height of the pipe can reach three meters;
• according to SNiP 2.04.01-85, it is strictly forbidden to combine sewer ventilation with other ventilation systems of the house and chimney;

• the distance of the windows to the outlet of the waste pipe must be at least four meters;
• Ventilation can only be done on the roof, and not in the attic. The exception is certain cases when the house has two drain pipes. One of them can be placed in the attic, but a ventilation valve must be installed;
• the ventilation section that runs in the attic must be insulated;
• It is prohibited to lead the end of the pipe under the roof overhang, since when snow melts in winter, the system may be damaged.

Compliance with these rules will allow you to avoid a number of problems and troubles during the operation of the sewer system.

Alternative to a drain pipe

There are situations when the ventilation of the riser does not work effectively, for example, if it is old and clogged. Sometimes it may be absent altogether, for example, in a private house.

The situation can, of course, be corrected by replacing the system or installing it. However, this work is quite labor-intensive and time-consuming.

Replacing the drain pipe in an apartment can be done independently. But the replacement of the area in the attic and on the roof should be carried out by the appropriate services that have permission to do so.

Therefore, it is more advisable to use its alternative - a sewer aerator or, as it is also called, a check valve. True, the last name is incorrect, since sewer check valves are devices that prevent the penetration of waste from the riser into plumbing fixtures in the event of an accident.

The aerator provides air suction into the system to stabilize the pressure, just like ventilation of the riser. At the same time, it prevents gases and air with unpleasant odors from escaping outside, so it can be installed even in an apartment. The price of such a device is about 100-150 rubles, which is an order of magnitude less than the cost of installing a drain pipe.

It should be noted that the sizes of aerators vary. The purpose of the device depends on them:

Finally, I will give the basic rules for installing an aerator in an apartment or house, which must be followed for the device to work properly:

• the device must be installed after the last plumbing fixture in the system, with the device closest to the riser being considered first;
• the valve must be positioned higher than other plumbing fixtures;
• in cases where a drain is used in the system, the aerator must be located at a height of at least 35 cm above the floor.

Ventilation valves are not intended exclusively for indoor use and are therefore prohibited from being taken outdoors.

As for installation, this procedure is extremely simple - the device is inserted into the socket of the sewer pipe. To ensure a reliable connection, the joint should be coated with sealant.

Here, in fact, are all the basic instructions for connecting the aerator.

Conclusion

A drain pipe in a multi-storey building is a necessary element of the sewer system. In addition, as we found out, in some cases it is also necessary in private homes. However, sometimes a sewer aerator can be used instead.

You can get additional information on this topic from the video in this article. If you are having problems with your sewer system venting that you cannot fix, please ask questions in the comments and I will be happy to try to help you.