Those times, when the amenities in the suburban areas were in the courtyard, fortunately, are long gone. Almost every owner of a private house prefers to equip the sewage system today. Moreover, its installation is usually not too expensive. In this case, plumbing fixtures are installed directly inside the building and connected to a common riser. Drainage of effluents from the house is carried out along highways of the external sewage system. Of course, when assembling an external system for the removal of contaminated water, certain standards and technologies must be strictly observed. Otherwise, in the subsequent owners of the house there will be a huge number of completely unnecessary problems.
Installation of external sewage: features
Before proceeding with the actual assembly of the external wastewater disposal and disposal system, it is, of course, necessary to draw up a detailed design and make all the necessary calculations. When developing a scheme of external sewage, you must definitely decide on:
Necessary materials and equipment
Installation of the external sewerage of a country house is carried out using:
large diameter pipes;
related materials (fittings, insulation, manholes);
a septic tank or materials needed to equip a cesspool (cement, gravel);
if necessary a fecal pump.
Which pipes to choose
The first thing to decide when drawing up a project for the external sewage of a country house is, of course, with a variety of highways themselves. Modern industry offers mainly two types of sewer pipes: cast iron and plastic. The first option in private homes is used quite rarely. The fact is that cast-iron pipes, firstly, are expensive, and secondly, are susceptible to rust and are fragile. In addition, such highways are difficult to mount. After all, the weight of cast-iron pipes is significant. They can only be installed using special equipment.
Plastic sewer pipes are completely devoid of all these shortcomings. Among their advantages, among other things, include:
Light weight. No special equipment is needed when installing plastic lines. Installation of such pipes in trenches can be carried out even by just one person.
Low cost . The price of plastic pipes is much lower than that of cast iron.
Smooth inner surface . In these pipes, when properly installed, sludge and blockages never form.
Plastic lines serve a little less than cast iron. But all the same, as manufacturers say, they can lie in the ground without the need for replacement for a very long time - up to 90 years.
Sometimes the installation of an external sewage system is also carried out using asbestos-cement or ceramic pipes. And that, and another kind of highways can last a very long time. However, asbestos and ceramic pipes, as well as cast-iron pipes, are quite difficult to lay in trenches due to their heavy weight. Yes, and they are quite expensive.
Types of plastic highways
To assemble the external sewage of a private house, pipes can be used:
Corrugated polyethylene . The main advantage of highways assembled from pipes of this variety is increased strength.
Polypropylene Such pipes do not differ in special strength, but they can withstand very high temperatures. They are used more often nevertheless for the assembly of internal sewer systems.
Polyvinyl chloride. This variety of highways is characterized by high strength and the ability to easily withstand winter cold.
Most often in suburban areas for laying an external sewer system, a PVC pipe is thus used. In terms of strength, such lines are slightly inferior to corrugated polyethylene, but at the same time they are much cheaper.
In turn, polyvinyl chloride pipes are divided into three classes:
light (can not be laid under the roadway);
medium (can be mounted under the carriageway with not too heavy traffic);
heavy (can also be used for laying industrial networks).
In suburban areas, pipes of light or medium strength are usually used.
What should be the diameter
Sewage flows through the sewer system of a country house, containing rather large particles of dirt and waste. It is in connection with this that the use of pipes of a rather large diameter is what the SNiP standards prescribe in this case. External water supply and sewerage should be laid, of course, taking into account the needs of the people living in the house. However, the diameter of the drain line, according to the standards, in any case should not be less than 100-110 mm. The latter option is considered the most preferred. If the sewerage is equipped at once for several suburban buildings, pipes with a diameter of at least 200 mm should be used for laying external highways.
What can be a septic tank
When designing an external drainage system at home, among other things, one should also decide on the type of sewage receiver. Of course, the laying of the external sewage system can be carried out in a regular cesspool. However, in this case, the owners of the house will subsequently face many problems, such as, for example, unpleasant odors or the need for periodic calling of the cesspool machine. Therefore, most owners of country houses today prefer to use a special device, a septic tank, as a wastewater receiver. The most popular types of such equipment, there are only two:
The first type of receivers is two (and sometimes more) interconnected concrete rings installed in pits. In the first of these, wastewater is purified from the largest particles. The bottom of this well is concreted. In the second receiver, the remaining liquid part settles completely.
Installation of external sewage networks using a concrete septic tank has the advantage of being very inexpensive. However, in simple concrete rings, wastewater, of course, is not particularly effectively treated. In addition, the cesspool machine in this case, albeit less often than when using a cesspool, but most likely, it will still be necessary to call from time to time. Therefore, most often, owners of suburban areas use more advanced factory septic tanks to dispose of plums from the house. Such models are not only effective in operation and long service life, but also easy to install.
Inside each factory septic tank there are several compartments in which waste water is separated and sedimented. Also in the case of modern models there is a special microflora that promotes the decomposition of feces and waste into components that are odorless.
How to choose a place for a septic tank
Install the receiver on the site, installing the external sewage system, taking into account the following factors:
Choosing a place for a septic tank should be such that the drain line from the building to it could be drawn in a straight line. In this case, the sewer system will work as efficiently as possible - without blockages.
Excavation pit for septic tank
The dimensions of the pit for the receiver depend, of course, primarily on the dimensions of this particular model. Excavate pits under septic tanks, usually using special equipment. But, of course, if desired, the owner of a country house can save and carry out earthwork on his own. In any case, the pit should be oriented in such a way that the inlet pipe of the septic tank is subsequently located in the direction of the building.
Pipe laying rules
External water supply and sewerage networks, of course, must be installed taking into account certain standards. So, trenches under the drain line are dug out according to SNiP exclusively below the level of soil freezing. Some owners of suburban areas do not adhere to this rule and lay pipes at a shallower depth, insulating them with mineral wool or other insulators. Such a sewage system can also work quite effectively in the winter. However, in this case no one can give guarantees that at one fine moment the highway will not freeze.
In private houses, basically two types of external sewage are installed: gravity and pressure. In this case, the first option is used most often. When arranging gravity sewage, pipes are laid with a slight bias towards the septic tank. That is, the sewage in such a system leaves the house in the receiver under the influence of the natural force of gravity.
The pressure system in a country house is mounted only when there is no possibility to stretch the highway with the necessary slope. In this case, the fecal pump is additionally included in the system. Such an external sewage system allows with a high degree of probability to avoid the appearance of blockages. However, in this case, the owners of the house, for obvious reasons, have to increase energy costs.
At what angle should pipes be laid
Below we present to the attention of the reader a table from which you can learn about how to correctly mount the trunk of an external sewage system at home with one or another of its diameters.
The necessary slope when laying pipes of the external sewage systemPipe diameter | Optimum slope | Minimum Slope |
100 mm | 2 centimeters per linear meter | 1.2 cm |
150 mm | 1 cm | 7 mm |
200 mm | 8 mm | 0.5 mm |
Thus, the slope of the external drain lines should not be too small. Otherwise, the water pressure in the gravity system will not be sufficient to move large particles into the septic tank. However, the slope of the sewer pipe of the external sewage system at home should not be made very large. Otherwise, water will flow through the pipe very quickly, and solid particles will begin to linger inside it. Which, of course, will also lead to frequent blockages. When arranging an external drain of a private house, it is best, therefore, to adhere to the optimal indicators of the slope of the highways towards the septic tank.
Manholes
Sometimes it happens that in a straight line the drain line to the septic tank cannot be laid. In this case, the external sewage of PVC (or any other) must be mounted so that all the elbows in it are connected at an obtuse angle. Otherwise, the highway will be constantly clogged. Over each knee in such a system, inspection wells are arranged to facilitate maintenance. The latter in most cases are ordinary plastic rings or large diameter pipes with a cap.
External sewage: issue price
When developing a project for a sewer system at home, an estimate of all future expenses is usually compiled. The total cost of laying sewage depends on many factors, the decisive of which is the number of people living in the house and, accordingly, the volume of water used by them. In general, when calculating the cost of external sewage, the following are taken into account:
Also, the total cost of laying the system may depend on the need to use a fecal pump, as well as various kinds of additional elements. A PVC pipe with a diameter of 110 mm costs about 150-180 p. (over 10 m). The price of a small septic tank "Tank" for 1200 liters is about 25 thousand rubles. For a fecal pump, depending on the brand and performance, you will have to give from 7 to 25 thousand rubles.