Sewerage of any private home needs ventilation. The proof of this is the "strange" sounds, gurgling and stench, which penetrate the plums in strong winds or in hot summers. Investments in arranging the ventilation of the sewerage of an apartment building and a cottage will preserve the coziness and pleasant atmosphere of the home, without too much ruining the budget.
Siphon and odors
Some owners doubt whether ventilation is needed in the sewerage of a private house. And they are convinced of its necessity when the stench spreads from the bathrooms and the kitchen throughout the house.
The composition of the sewage is heterogeneous, so fermentation processes are constantly going on in the pipes, accompanied by gas formation. To prevent the smell of sewage from venting, plumbing drain holes are equipped with a siphon (water seal).
With perfect sewer operation, the siphon is filled with water to a certain level. If some time they do not use plumbing, the water level drops, organic vapors spread throughout the room.
Ventilation is needed to balance the pressure in the drain system.
Disgusting odors and gurgling are also explained by the fact that when the feces are washed off, pressure drops in the pipes. Liquid from full siphons is drawn into the pipes and nothing prevents the stench.
There is only one way to avoid the appearance of vacuum plugs - the ventilation system of the sewer system.
Do you need sewage ventilation in a private house?
Building standards allow the use of sewage without ventilation in houses no higher than 2 floors with a small amount of sewage.
If the volume of drains overlaps the cross section of the sewer, ventilation is mandatory for sewage.
The drain will not overlap when one plumbing device is simultaneously operating in the house. For example, the standard diameter of the toilet drain is 7 cm, and the diameter of the pipe is 11 cm. But if two toilet bowls are simultaneously drained, the sewage system will be closed. For information, the diameter of the drain pipe of the bathroom or washbasin is 5 cm.
Having calculated the possible salvo discharge of all the plumbing at home, it becomes clear whether sewage ventilation is needed in a private house.
Sewerage ventilation must be equipped if:
- the diameter of the risers is equal to or less than 5 cm;
- the house has two or more floors, bathrooms and washbasins are located on all floors;
- in the cottage or near it there is a pool or a large bath.
Another argument in favor of a ventilation scheme for the sewerage of a private house: modern siphons are often of very small volume and the water contained in them can dry out in a few days.
Owners returning after a brief absence will be unpleasantly surprised by the unpleasant smell in the house.
The fan pipe in this case plays the role of a chimney. Due to the pressure difference, air from the sewer is diverted to the street.
Fan pipe
The main thing in the ventilation system of the sewage system of a private house is the fan pipe. It takes “odorous” gases out.
Usually, when designing a house, a channel for a fan pipe is provided.
Rules for the location of the fan pipe:
- The end of the fan pipe extends beyond the roof by at least half a meter;
- The distance to the windows and balconies is at least 4 meters so as not to disturb the smell;
- It is forbidden to bring the fan pipe into the general ventilation;
- It is possible to combine the sewer risers with one pipe for ventilation;
- It is not advisable to remove the ventilation riser under the eaves of the roof. There is a high probability of breakage by snow sliding from the roof;
- The head of the pipe is covered by a ventilation umbrella for sewage. A ventilation umbrella equalizes the pressure in the sewers, protects the system from rain and snow. Unlike deflectors, ventilation umbrellas for sewerage are resistant to icing in the cold season.
According to the rules, each sewer riser is ventilated separately. To do this, the fan pipe is mounted on the riser furthest from the exit of the sewer from the cottage. A septic tank will be ventilated through it. Vacuum valves are installed on the ends of the remaining risers for ventilation.
Fan pipes for each riser make up the optimal ventilation scheme for the sewerage of a private house.
Materials and installation of sewer ventilation
Depending on the outputs, two schemes of ventilation of the sewerage of a private house are possible:
- Insulated or insulated;
- Uninsulated.
The first option is widely used in areas with harsh climates.
In private homes, PVC pipes are used for ventilation of the sewer, which are inexpensive, tightly connected to each other, easy to install.
The diameter of the section of the fan pipe should be selected greater than or equal to the section of the riser, from 5 cm in a 1-storey building and from 11 cm in 2 or more.
The diameter of the insulated riser at the exit is about 16 cm.
Diameter of pipes for sewage ventilation in an apartment building and a cottage for:
- eyeliner for sinks or bidet 3 - 4.5 cm;
- kitchen sinks, showers, bathtubs - 5 cm;
- toilet bowls 11 cm;
- risers 6.5 - 7.5 cm.
Sewerage ventilation in apartment buildings, connecting 2 or more risers, is made of PVC pipes up to 20 cm in diameter. To connect the collectors and wells, pipes of even larger cross sections are used.
Vacuum Ventilation Valves
Valves are used as an alternative or addition to a fan pipe. This is the way out if the house is already built, but ventilation is provided.
Ventilation valves should not freeze, they are usually installed in the attic. The mechanism of action of the ventilation valve for sewage is very simple. Its lumen is hermetically covered by a membrane held by a weak spring. When water is drained, air is discharged in the riser, the membrane moves away and starts the air inside the sewer system. The pressure in the pipe equalizes and the valve closes automatically. Thus, the valve is open only when it is necessary to start the air from the room into the pipes.
Some owners prefer installing a vacuum valve to vent the sewage system directly in the bathroom or toilet. In this case, it is important to provide access to it for control.
The valve should be 30 - 35 cm above the floor.
Valve for ventilation of the sewage system can be assembled independently.
Materials and tools:
- fountain pen spring;
- end tee;
- 45 mm self-tapping screw;
- polyethylene lid for a glass jar;
- a small sheet of thin foam;
- glue;
- awl.
Progress:
- We cut a circle with a diameter of 50 mm from the lid, screw a self-tapping screw into the center;
- From the foam rubber we cut a circle of a slightly larger diameter and glue it to the plastic mug, pulling out a self-tapping screw;
- In the end tee we make holes with a diameter of 5 mm at intervals of 25 mm, pierce the hole with an awl and insert a self-tapping screw;
- Now we unscrew the screw and collect the finished valve.
If the valve is assembled correctly, air blown into the holes will pass freely. The width of the slit is regulated by a self-tapping screw.
Unfortunately, a vacuum valve can only partially replace a complete ventilation system.
After a while, it may become clogged or broken. And the valves are absolutely useless when the hydraulic locks dry out.
A fan pipe prevents the absorption of water traps from siphons into pipes and very effectively prevents the smell of sewage.Ventilation reduces the stench and drying out of water gates, characteristic of showers and gangways.
Drain plumbing equipment must contain a water seal. Even with a competent ventilation device of a private house, part of the unpleasant odors can penetrate through the drain without a water seal.
Sewer ventilation
Sometimes even a competent scheme does not provide high-quality ventilation of a sewage system in a private house. If the supply is too long (more than 3 m), ventilation is required.
To solve the problem, you need to increase the cross section of the eyeliner. So, the calculated indicator of 4 cm increases to 5 cm with a length of 3 meters.
If the eyeliner is 5 meters, the diameter increases by 1 \ 4. It will be necessary to increase the cross-section of the eyeliner with a height difference of 1 to 3 meters. An increase in diameter is also required when, when connecting to the toilet, the height difference is more than 100 cm.
If this method does not work, you will have to equip the additional ventilation of the sewerage of a private house in the form of a vacuum valve or an additional fan pipe.
Video about whether the sewerage of a private house needs ventilation and how it should be arranged:
