Sewer ventilation in a private house - the path to comfortable living

Any person living in a private household at least once encountered a problem when, in strong winds or hot weather, "ambergris" from the sewer penetrated into the dwelling. The gases formed as a result of the decomposition of organic matter smell unpleasant. In addition, you are probably familiar with sewer gurgling and "champing" when draining sewage. This is due to a change in pressure in the sewer system and the formation of vacuum plugs. All these troubles are eliminated in a private house.

Ventilation is necessary for any type of sewerage: centralized, autonomous, isolated or non-isolated. It will not only provide the required volume of fresh air, but also balance the pressure of the system, due to which the drains will merge silently. The sewer hood should ideally be designed during construction in a private house. In practice, it happens that attention is paid to its arrangement only when guests make a comment about the fragrant persistent aroma in the room or on the site.

Ventilation schemes

When sewer ventilation is planned when designing a house, it is most often done inside the house. In this case, the riser is brought to the roof in the form of a fan pipe. It is, as it were, a natural extension of it. The diameter of both pipes must match (if the riser is 110 mm, then the fan pipe is 110 mm). The ventilation duct is thought out in such a way that the fan pipe is located away from the windows (at least 4 meters) in order to timely naturally eliminate unpleasant odors.

The height of the fan pipe above the roof depends on the type of roof and varies from 0.2 to 3 meters. Its height is regulated by the set of rules SP 30.13330.2012. For example, for a flat roof of a country house, at least 300 mm of elevation is required, and for a pitched roof, about 500 mm. From above, ventilation is equipped with a deflector, which acts as a sewer protection against the penetration of precipitation and to enhance air draft. In general, the deflector increases the efficiency of the ventilation system in the house.

Experts do not recommend connecting the ventilation riser to the pipes of the chimney or the common house exhaust system. But it can combine approaches from several sewer risers. When the vent pipe is led out sideways (into the wall), it is not placed under the roof overhang, since there is a great danger in winter that the outlet will be disrupted by an array of snow or ice. It is also recommended to hide the outlet opening behind a decorative rosette.

Non-standard ventilation schemes

The classic way to create a sewer ventilation system has been described above. However, if the building has already been built, such a hood is difficult to implement. In a private household, sewer ventilation can be external. There are three schemes outside the house exhaust system:

The main issues related to the aeration plant

Most often, people living in private households have doubts or questions regarding the creation of a ventilation system in their sewers. The main topics are:

Will ventilation cope with its functions in hot summers, during the maximum decomposition of organic waste?

Yes, it will. This is due to the difference in external and internal temperatures between the treatment plant and the environment, due to which there is a constant heat and air exchange. The sewer water temperature will always differ from atmospheric air. This factor also contributes to the creation of a pressure difference in the installation and its effective ventilation.

Will the riser, which is an uninsulated (non-insulated) part of the structure, freeze in winter?

In winter, wastewater is always warmer than air, so the riser cannot freeze over with regular use of the treatment plant. In some regions, the riser facing the street should be insulated (insulated). For this, a pipe with a large diameter is used. For more detailed information, it is better to contact professionals.

Some time after the installation of aeration, odors began to penetrate into the rooms. Why?

Siphons filled with water tend to dry out, letting in an unpleasant odor. This happens if the sewer has not been used for a long time: the riser accumulates rarefied air. There are several ways to solve: change (increase) the volume of siphons, install fan pipes or an aeration valve on the riser. The valve will allow you to efficiently conduct atmospheric air inside and prevent air discharge in the pipes.