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Installation of sewerage from plastic pipes held in private and apartment buildings, administrative buildings equipped with running water. Sewage disposal systems are divided into local and centralized. In one room, the wiring consists of blocks, each of which consists of 3 lines - from the toilet, bathtub and kitchen sink. When constructing a highway, parts of various lengths, diameters and configurations are used. Let's consider what nuances should be taken into account when designing and assembling a pipeline with your own hands.

Principles of installation of sewerage from plastic pipes

Selection of materials for sewerage

When planning the laying of new communications for drainage, it is necessary to pay special attention to the choice quality material, accessories and components. It is recommended to purchase goods from a trusted supplier who has a certificate for their products. It is better to buy products produced by one manufacturer. This will avoid difficulties when fitting and connecting parts.

The basis for the calculations is a diagram that displays the following data:

  • riser;
  • inspection hatch;
  • tee;
  • horizontal purlins;
  • corners;
  • water seals (siphons);
  • adapter;
  • bends;
  • water consumers.

It is advisable to purchase material 10-15% more than calculated. In any work, defects and mistakes are possible. Except plastic products, you need to buy silicone-based lubricant. It is best suited for connecting parts of the highway and ensuring its tightness.

Why are plastic pipes better?

When choosing a material for sewer installation, most craftsmen are inclined to use pipes made of polymer plastic. This decision is justified by the many positive characteristics inherent in this product of the petrochemical industry.

The installation of polyvinyl chloride pipelines has the following advantages:

  1. Affordable price. It is an order of magnitude lower than that of metal structures.
  2. A light weight. Plastic pipelines do not place additional load on walls and floor slabs.
  3. Easy to assemble. There is no need to use expensive equipment to connect parts.
  4. Resistant to corrosion, mildew and mildew.
  5. Long service life. It is at least 50 years old.
  6. Presentable appearance. The products fit well into any interior.
  7. Elasticity. Pipelines do not break under vertical and horizontal loads.

Polymer communications do not require regular maintenance and repair.

Preparatory work

To lay a pipeline for drainage, you will need special equipment for laying the channel required configuration in floors, walls and furniture.

It is necessary to use the following tools and devices:

  • oil or diamond level;
  • a hammer drill with a set of drills, impact bits and a diamond bit;
  • roulette;
  • hammer;
  • chisel
  • marker;
  • Silicone Grease.

Preparation for sewer installation begins with drawing a horizontal line from the entrance of the tee to the riser to all water consumers. After this, marks are made every 50 cm corresponding to the required slope. To avoid mistakes, during assembly, supports are placed on which the pipes will be laid. Holes are drilled in the walls into which clamps with a diameter corresponding to the pipes are installed. Finally, holes are drilled, the bed is cleared and construction debris is removed.

Features of internal wiring

The peculiarities of sewerage arrangement are that the basis for its functioning is home sewer is the force of gravity. Waste products move through the channels by gravity under the influence of gravity. In order for waste from the water consumer to enter the riser, all lines must have a slope of 1-1.5%. So, with a line length of 200 cm, the height difference between the outlet and the outlet of the pipe into the general drain should be 2-3 cm. For each turn, another 1 cm is added. If these rules are not followed, the line will constantly become clogged with waste.

The next nuance is the selection of the correct cross-section size and line configuration.

You should choose plastic sewer pipes of the following diameter:

  • riser, tee, outlet and corrugation from the toilet - at least 100 mm;
  • line from the bathtub, washbasin and kitchen sink - 50 mm;
  • drain from washing machine and dishwasher- 32 mm.

Since the largest waste products come from the toilet, the distance from it to the riser should be minimal. If you need to change their direction to lay pipes, it is better to do this using 45° bends, since sharp turns can become clogged.

Adjusting workpieces to size

Features of products from polymer material is a change in their size under the influence of temperature. So, when it increases by 1°, the length of the link increases by 0.5%. This must be taken into account when making calculations so as not to install turns close to the walls. You should always leave 1-2 cm of margin for damper expansion of the links. Slight curvature does not affect the strength and tightness.

When cutting blanks, it is necessary to check that the diameter of the pipe corresponds to this indicator of the fittings used when laying communications. Technical indicators are printed on the products themselves, but it is better to check them in advance, even before assembly begins. It should be remembered that joint tightness and tightness are achieved through the use of gaskets. The difference between the inner and outer diameters of the connected links is 2 mm. A slight backlash allows you to compensate for minor errors made during design, marking and assembly.

Joint in socket

Let's look at the features of connecting plastic pipes. They are made using sockets, inside of which rubber gaskets, rings and cuffs are installed. Double gaskets with a plastic ring are considered the best in terms of durability. They are difficult to assemble, but the effort made pays off in the reliability and durability of the joint. Before connecting the parts, you need to make sure that the elastic is of the correct shape, tightly located in the groove of the socket and is not skewed. If the product is defective or damaged during assembly, it should be replaced with a serviceable part.

The attachment points are the weakest points of the pipeline. Over time, the cushioning material dries out and decreases in volume. To slow down this process, it is necessary to use high-quality lubricant with a preservative effect. Soap and car oils are not suitable for this. These substances cause rubber corrosion. Professionals recommend using silicone grease.

The edges of the sawn pipe must be cleaned to obtain a chamfer. After the segment is inserted into the socket, it must be pushed forward as far as it will go and pushed back 10-15 mm.

How to do the installation?

In a private house, you can make several risers, connecting them into one line or leading them to different septic tanks via separate lines. The main condition is compliance with environmental safety rules.

When installing sewer pipes It is recommended to follow these rules with your own hands:

  • use a hacksaw for cutting workpieces;
  • insert the pipes into the sockets without distortions, perpendicular to their cuts;
  • assemble the drainage system in the direction from the tee to the sources of water consumption;
  • control the level of each stage of assembly;
  • do not fill the highway with concrete, it is better to cover it with plastic, which is easy to remove;
  • do not forget to lubricate the joints and leave a damper gap.

If the rules for calculations, marking and assembly are followed, the sewer system will last no less than the building itself.

The comfort of residents of an apartment or private house is impossible without a high-quality sewer system. Imported furniture and chic designs in the rooms mean nothing if the drains are leaking. Therefore, before laying a water supply system, proper installation of sewer pipes is required. pvc pipes or structures made of cast iron. Let's consider the features of working with a plastic pipeline, since outlet communications are increasingly made of PVC. We'll tell you about the algorithm of work, share the secrets and tricks of professionals.

Selection of materials for sewerage

In 99% of cases, when installing sewer systems, plastic pipes (polypropylene, polyvinyl chloride, polyethylene) are used. The advantages of communications made of synthetic materials are lightness, ease of assembly, resistance to hydrothermal loads and corrosion, and durability.

PVC products are most often used when laying sewers

Note: For sewer structures you can use plastic parts much smaller thickness than for water supply, since the pressure is lower.

Diameter is the key factor to consider. This value depends on the type of plumbing equipment. Minimum diameters:

  • bidets and sinks – from 32-40 mm;
  • showers and baths – from 50 mm;
  • if more than one device is supposed to be connected to the pipe - from 70-85 mm;
  • main risers – from 100 mm.

Before you begin installing sewer pipes with your own hands, draw up detailed diagram future communication system with calculations of consumables. Calculate the number and footage of parts and fittings.

Treat joints and fastening points with fittings with sealants for strength.

Using a common drain for several plumbing fixtures will save money and space in the room, and the result will be more aesthetically pleasing. Select the desired pipe diameter based on the recommendations above - sink, bathtub, washing machine can be connected to one pipe going to a common riser. The toilet must be connected directly to the riser - separately.

Preparatory work

It is possible to dismantle sewer pipes and lay new communications in a private house within a day to several days, in an apartment - from 1-2 to several hours. An illiterate approach and lack of a plan will drag out the event for weeks. Therefore, prepare thoroughly before starting work.

  1. Determine the type, location and quantity of plumbing fixtures, pipes and fittings.
  2. Make a diagram.
  3. Calculate the stock additional details required for the functioning of the system (meterage of the structure, consumption of mixtures and fittings, consider with a reserve).
  4. If in the future you plan to install additional plumbing with a sewer drain, it is rational to leave a drain for it with a plug. Otherwise, you will have to change the system and dismantle the sewer pipes again.
  5. Buy consumables.
  6. According to the diagram, calculate the length of the sections, cut the pipes, taking into account the dimensions of the purchased fittings.

When marking a PVC product, make marks around the entire circumference

How to cut and strip PVC pipes

To cut plastic parts, just as when installing cast iron sewer pipes, use a hacksaw.

Cutting algorithm:

  1. Mark the location of the cut in a circle - this will ensure a smooth edge, which will ensure the tightness of the joints.
  2. Cut strictly at a 90° angle.
  3. Then clean the ends with sandpaper or a knife.

Keep in mind that the drainage system is installed on a slope, since the sewerage works based on the force of gravity. Fix the slope with brackets on the walls. You need to buy them in advance along with other materials.

Installation of sewerage from PVC sections

To avoid leaks and inconsistencies, when assembling the sewer system, it is recommended to move in the direction from the riser to the plumbing fixtures.

Attach the PVC communication to the wall every 100 cm, this will prevent subsidence and breakage

Instructions for installing sewerage from plastic pipes:

  1. Mark the axes of pipelines, places of fastening to walls and other surfaces.
  2. Assemble fasteners from pipes, pipes and fittings using sealed rubber bands. Insert the parts into each other until they stop. Make sure that the surfaces to be bonded are clean. Dirt will break the seal of the connection. And this leads to leaks and the appearance of an unpleasant odor due to moisture condensation (at joints, from sinks, bathtubs and the sewer itself).
  3. Connect the structural parts, check the horizontal and vertical to ensure that the fastenings are level and secure.
  4. Fasten the products with clamps, lay horizontal structures to siphons and plumbing outlets.

Tip: to improve the tightness, craftsmen advise lubricating the ends of the segments with non-acidic sealants, soap solution, auto sealants or glycerin-based lubricants.

  1. When the system is assembled, connect all the plumbing fixtures one by one, including siphons from the bathtub and sinks.

Rules for laying sewerage indoors

Try to reduce the number of joints and turns; seamless communication is more reliable and durable. Every fastening point is a potential threat of future leaks; turns increase the risk of blockages.

For a high-quality result, follow the rules for installing sewer pipes:

  1. When working with plumbing fixtures, take into account the characteristics of the material; each mixing unit has its own technology.
  2. When calculating the diameter of products, take into account the slope angle and the number of connected devices. In the area of ​​connection to the riser, use a diameter of 100-150 mm.
  3. Direct the sockets of the riser and horizontal sections towards the flow Wastewater.
  4. If, before laying new communications, sewer pipes in an apartment or house were dismantled, use plastic parts of the same diameter as the old ones.
  5. For horizontal wiring, it is allowed to use a diameter of 100 mm, as in the case of a toilet riser; for other single fastenings, 50 mm is sufficient.
  6. The slope of the system should be 4-7 cm per 1 m.
  7. To prevent the sewer from sagging, attach sections to the walls every 100 cm.
  8. Be sure to include fan ventilation in the drawing. This will help regulate the pressure in the drain compartments and get rid of unpleasant odors.

Preventing blockages in PVC pipes

Despite the fact that in the event of a breakdown, removing PVC pipes is easier than dismantling cast iron sewer pipes, this is a troublesome undertaking and costs money. To avoid having to tear down or replace installed communications in the event of a blockage, provide “cleanouts” with plugs. Another preventive measure is additional vertical outlets for air check valves(a diameter of 50 mm is sufficient).

To clear possible blockages, leave the inspection with a plug - this will simplify access to the clogged area

Inspections with removable covers when installing pipes for external sewerage are installed every 15 m. For internal systems– at the junction of horizontal sections with a riser. This step will make it easier to clear the drain if it becomes clogged.

How to test your sewer

Upon completion of work, conduct leak tests of the sewer system.

Verification options:

  • turn on all existing plumbing fixtures at the same time;
  • Fill a bucket of water, pour it in one gulp into the sink, then into the bathtub.

During the inspection, examine all joints and connections. If no problems are found, the test is successful. If there are leaks, seal and re-treat the problem areas with sealants or construction adhesive. After the insulating substances have dried, perform the tests again.

During tests, pay attention to joints and fastenings to fittings

Video: installation of plastic sewer pipes

Connection washing machine sewerage, in our time, is a fairly simple and inexpensive matter. Any DIYer can handle connecting the machine to the water seal under the sink, but it happens that the drain needs to be connected to the riser.
The easiest way to do this is to top floor apartment building, since in this case, there is no need to negotiate with the residents of the house. Otherwise, you will have to go around to all the residents living above and ask them not to use the sewer during the work.
Let's look at the drain insert in more detail using an example.
As a rule, the riser has a diameter of 110 mm. In the example below, the pipe diameter is 50 mm, it consists of two parts and is located on the top floor. Therefore, when you make your insert, you should take into account the design features of your particular riser. This applies to the diameter and possibly additional parts not described in the example.


For insertion you will need the following tools and parts: a hacksaw, a stationery knife, a tee with a branch diameter of 50 mm and an angle of 45 degrees, a compensation pipe and a cuff for inserting the drain hose of the washing machine.


First, preparatory work is carried out. The rubber o-ring is removed from the branch of the tee and a cuff is inserted in its place.


Next, the tee and expansion pipe are assembled together.


The assembled parts are applied to the insertion site, so that the lower edge of the tee lies at the level of the beginning of the pipe expansion. The length of the cut section is marked on the riser. On the compensation pipe, in this case, there are marks by which you can easily measure the cut section of the riser (along the top mark on the compensation pipe).


After preparatory work, you need to agree with the residents living above you so that they do not use the sewer system during the work.
The actual work on inserting the drain should be carried out as quickly as possible, because you are not insured against the fact that one of the residents living above will forget about the agreement with you and drain the water into the sewer.
Next, cut off the marked section of the riser.


Remove the shavings and use a utility knife to chamfer the outside of the pipe.


Insert the tee into the downpipe of the riser. Insert the upper part of the riser into the tee. Install the expansion pipe by bringing all the pipes together. The pipes must be inserted into each other all the way down, so that over time they do not move down under their own weight or as a result of mechanical stress.
TIP: Wet the ends of the pipes with water - this will make it easier to assemble the pipes together.

Often, in the process of replacing a pipeline, you have to deal with the fact that the diameter of one end of the line is 110 mm, and the cross-section of the other is larger or smaller. And how to replace a sewer riser? A compensator will come in handy - an excellent transition device, specifically designed for connecting elements with a difference in cross-section.

By definition, a compensator is a device for compensating linear extensions of a pipe system. Each material has individual linear expansion indicators, so an expansion joint is not needed for every pipe line. The relevance of the element increases if there is a sewer system hidden in the screed or wall. By appearance The element is a corrugated pipe equipped with connecting flanges on both sides.

Important! The use of flanges is shown for pipes with a cross-section of 63-110 mm; for pipes with a diameter of up to 63 mm, a threaded compensator is available, as well as an element equipped with a rubber corrugated seal and a union nut.

A plastic sewer compensator is indicated for repairing/replacing a PVC pipe riser without dismantling the entire system. Representing a piece of a curved shape, the compensator has the same cross-section as the elements of the main line and is inserted by cutting out the piece and fusing the compensator with a blowtorch.

Advice! Compensators are mounted only on sewer structures or water pipes for hot water.

Often, the installation of an element is required to renovate a bathroom or toilet room, when differences in floor level require raising or lowering the cross on the riser to arrange the angle of drainage into the sewer.

Features of the sidebar


Polypropylene elements have almost universally replaced old metal ones sewer risers. Thanks to its undoubted advantages, plastic is becoming more and more in demand. However, in order to get a truly high-quality insertion result and install the compensator correctly, you need to take into account some simple factors:

  1. Take into account the thickness of the pipe walls;
  2. Calculate the length of the sewer line in order to calculate the approximate force of pressure on the welded (soldered) seams;
  3. For a pipeline with a cross-section of 110 mm, only flanged pipes are used;
  4. If pipes have a cross-section of less than 110 mm, it is most practical to use threaded connection, and it is better to choose pipe fittings PN 10, 16, installed when installing cold water supply systems - they are denser and more durable.

Important! It is very reasonable to provide thick pipe walls with increased strength, for which a welded installation method is used. Welding is also indispensable if the sewerage pipeline is intended to be used in conditions of increased temperature exposure.

Scheme of operation of inserting into a plastic riser:

  1. Cut out part of the pipe, treating the riser with a file to remove burrs;
  2. Cover the upper part of the pipe with sealant;
  3. Push the pipe all the way in;
  4. Cover the lower part with sealant;
  5. secure the compensator by inserting it into the pipeline socket;
  6. connect the system and secure the riser.

And advice: to connect a pipeline whose elements are made of them different materials A system of fittings equipped with a polymer coupling and pipe thread is used. Now you don’t have to guess why the pipe is needed and what to do with the PVC pipeline if it is leaky - the compensator will allow you to quickly and without much labor and time to repair the breakdown without disassembling the entire system.