Ventilation of a septic tank in a private house: is it necessary + tips for arrangement
The primitive cesspool has been replaced by septic tanks - elements of local sewage systems, within which biomass purification processes take place. Since the process of biological decomposition of organic substances releases gases that require exit from the chamber, ventilation of the septic tank is installed in a private house, ensuring the removal of gases and the elimination of unpleasant odors.
Agree, without such a device, the process of wastewater purification will not be complete, as a result of which unpleasant odors will begin to spread from the sewer.
If, when purchasing a ready-made sewerage system for a home, organizing ventilation is unlikely to become a problem, then if you build a septic tank yourself, you will have to put in a little more effort. In this case, the ventilation system will need to be designed independently. Further in the article you will learn how to properly build the ventilation of a septic tank with your own hands, and what requirements and standards must be observed.
The content of the article:
Ventilation of a septic tank - is it necessary?
Only with good ventilation can the entire local sewage system in a private home operate properly. In addition, ventilation of the septic tank is necessary not only for the removal of gases, but also for the further normal existence of the purified biomass.
If in the same cesspool When the wastewater accumulates, a natural process of purification occurs in the septic tank.
Often during installation homemade septic tanks, designed according to the simplest schemes, their ventilation is carried out naturally - through the cracks of the hatch. Over time, this leads to the rapid spread of unpleasant odors, both in the yard and inside the house.
For those who do not know why ventilation is needed in a septic tank, here are the following goals achieved when constructing ventilation:
- Providing microorganisms with oxygen. In the second compartment of the septic system there are aerobic bacteria that process wastewater after it enters the first container. It is these bacteria that are responsible for the effective purification of water, which will be impossible in the absence of sufficient oxygen access to the second reservoir.
- Creating a safe environment. When entering a living space, the resulting mixture of gases can pose a danger to human life. The mixture contains: carbon dioxide, hydrogen sulfide, methane and phosphorus compounds. Some of them are explosive, so their accumulation can lead to serious consequences.
The absence of a vent riser can lead to the failure of the toilet water seal, as a result of which the gas mixture from the septic compartment will rise into the house.
So, with each flush of water, an unpleasant odor will spread throughout the entire house, which will bring at least discomfort to all its residents.
The quality of biomass purification determines the characteristics of purified water, as well as the possibility of its further use. Often, liquid that has undergone three degrees of purification is used for watering the garden, washing the car and other household chores.
For all processes to proceed fully, it is necessary to ensure a direct flow of air to all tanks, which can only be done by good ventilation facilities.
Types of septic tank ventilation
The ventilation pipe can be installed both on the roof of the house and along its outer wall. The only condition is fan pipe should not be connected to the general house ventilation system, otherwise the exhaust gases may be mixed with air flows and penetrate inside the rooms. Depending on the location of the vent riser, there are two types of ventilation: internal and external.
For internal ventilation, the drain pipe located inside the house is a ventilation riser connected to the plumbing fixtures of the bathroom and toilet. Water is discharged in one direction, and a mixture of gases moves in the other, escaping far beyond the house.
With external ventilation, the pipe is located outside the house, and is often mounted to the wall of the house. The pipe is not connected to the plumbing riser, but is immediately included in the section of the drain pipe located from the house to the septic tanks.
In both cases, you will need two PVC pipes.The lower one will be installed in the ceiling of the sewer system, while its upper edge must be raised to such a height that melt water cannot penetrate inside.
The upper pipe, placed in the hole of the lower pipe, is fixed on the outer wall of the house with external ventilation. It can also be discharged onto the roof of the house, but only with internal ventilation.
How to make ventilation yourself?
Since one of the most reliable home-made structures is concrete septic tank, we will consider the process of creating ventilation specifically for this option.
The number of cameras will depend on the number of people living in a private house. So, for a family of 3-4 people it is recommended to build a three-chamber septic tank.
To ensure good ventilation, it is necessary to ensure the flow of air into the second chamber, where the process of processing waste biomass actually takes place aerobic bacteria.
As for the first chamber, only the main sewerage pipeline is connected to it.
Choosing a ventilation location
In most septic tank ventilation schemes, the pipe in the form of a straight vertical is installed high above the roof, directly above the bathroom. In real life, making an exhaust hood from a septic tank pit is quite difficult, since it is not always possible to install a pipe without bends. In two-story private houses, the task becomes even more complicated, because often there is a living room above the bathroom, which you would not want to spoil with such “decoration”.
It is not recommended to install the ventilation pipe under an awning or eaves.Otherwise, water, snow or ice will get inside the system. Also, do not lead the pipe into the attic, since the heated gases will spread to the lower floors.
The best option is to install a straight plastic pipe right in the center of the roof, thanks to which the ventilation system will be protected from precipitation.
If the pipe is installed in an unsuitable part of the roof, you can install a cap to protect it from precipitation. To prevent insects and small rodents from getting inside the pipe, it is enough to install a fine metal mesh.
You can protect the pipe from freezing by thermal insulation with mineral wool or polyethylene foam.
Installation of ventilation risers
During the construction of ventilation, it is recommended to install the riser at the beginning of the sewer line. This is necessary so that when flushing water, a vacuum does not form in the pipe. Its strength may be quite enough to inadvertently open the water seal in the bathroom.
Installing a ventilation inlet at the very beginning of the wiring will help to avoid catastrophic consequences, through which the vacuum will be successfully compensated.
With proper installation of septic tank ventilation, air flow occurs in the second septic chamber, passes through all pipes, and is discharged above the roof of the house. If everything is done according to the rules, then the residents of the house will not notice any unpleasant odors emanating from the ventilation pipe on the roof.
If the sewer system consists of cast iron parts, then it is best to immediately replace them with more practical plastic pipes. Essentially, you will need to dismantle the old system and reassemble the sewer network, but from special PVC pipes.
This will take a little more time, but will help to avoid the problem of overgrown pipes in the future, which will result in having to do double the work.
Conclusions and useful video on the topic
Visual instructions for the correct construction of septic tank ventilation are presented in the following video:
From this video you will learn how to make an effective septic tank for external sewage yourself:
The sewer system in a private house must be equipped with ventilation, allowing for the timely removal of gases that are formed during the processing of waste biomass. This will help not only protect your home from unpleasant odors emanating from the bathroom or toilet, but also increase the efficiency of wastewater treatment.
Despite the fact that the construction of a septic tank ventilation system is the final process, the design of the system is carried out in advance.
If you have previously had to install septic tank ventilation with your own hands, please share your experience with our readers. Tell us what type of ventilation you chose, what difficulties you had to face during the construction process. You can leave your comment immediately after the article, in the field provided for this.
