Installation of a sewerage system in a private house

Recommendation points

• Types of sewer pipes
• Sewer line design
• Laying and installation of pipes from the sewer well to entering the house
• Internal plumbing and connection to the central pipe

A properly planned and installed sewer system will ensure uninterrupted drainage of waste water for many years. Planning and laying sewer pipes is not difficult and can be done by hand. How to do it correctly, we will tell you in this article..

Types of sewer pipes

Sewer pipes are divided into 4 types depending on the material from which they are made.

Asbestos-cement and ceramic are now rarely found, so it makes no sense to discuss their advantages or disadvantages.

Cast iron pipes are still used for sewerage, but they are heavy, expensive and require certain skills during installation.

Plastic sewer pipes are several times lighter than cast iron. The inner surface is perfectly smooth and rarely clogs. It is easy to install the pipes; rubber gaskets are included in the package. According to materials and purpose, pipes are divided into three types:

1. Polyvinyl chloride (PVC) – used in gravity internal and external sewage systems. Durable and UV-resistant pipes.
2. Polyvinyl chloride unplasticized (PVC-NP) – used in internal, external, gravity and pressure sewer systems.
3. Polypropylene (PP) pipes have an estimated operational life of up to 100 years. Pipes are resistant to high temperatures and are preferred for internal wiring. Due to their weak rigidity, PP pipes are reluctant to be used for laying a drainage route in the ground.

Corrugated plastic pipes are used in industrial pressure sewer systems. It is not recommended to use corrugated pipes in a private house. The exception is corrugated pipes for connecting plumbing.

Sewer line design

When building a house, all rooms equipped with plumbing – kitchen, bathroom, toilet and shower are concentrated in the immediate vicinity.

Arrangement of internal sewerage involves the design of risers and piping in the room. A diagram of the premises is drawn on a sheet of paper, indicating the dimensions:

1. The place of passage of risers and drain pipes is determined.
2. The location of all plumbing facilities is noted, indicating the diameter of the outlet and the connection features. Turns, joints, elbows and tees are indicated.
3. On the shortest path, internal piping is supplied to the riser. Places of installation of fittings (tees, adapters, revisions, etc.) are marked on the riser..
4. Based on the drawing, the required footage and pipe diameter are calculated, as well as the required number of fittings.

1 – knee 90 °; 2 – straight tee 90 °; 3 – internal wiring pipe; 4 – plug; 5 – cleaning; 6 – non-ventilated riser; 7 – branch pipe; 8 – revision; 9 – ventilated riser

Consider a way of installing the internal wiring. The hidden method involves bricking the pipes in the wall or laying the route under the floor. The open method involves fastening pipes to the walls.

Laying and installation of pipes from the sewer well to entering the house

From the entrance to the house to the sewer well, a trench is planned with a slope in the direction of the drain. In the event that it is not possible to avoid problem areas, then in places prone to blockages, inspection wells are equipped, and the pipes are equipped with a revision insert.

A trench is being dug from the inlet sleeve of the sewer line, located in the foundation of the house, to the sewer well (cesspool, septic tank). For the normal functioning of the gravity sewer system, the slope should be 2 cm per linear meter when laying a pipe of 110 mm.

The bottom of the trench is carefully compacted and covered with a layer of sand or gravel 10-15 cm thick. After leveling and compaction of the sand or gravel cushion, the laying of sewer pipes begins.

From the inside of the house, a pipe is inserted into the sleeve. The bell points towards the inside of the house and the smooth side towards the outside. The smooth end is lubricated with a special compound or waterproof silicone and the socket of the next pipe is pushed onto it until it stops.

Two 45 ° bends are used to turn the track 90 °. 15 ° and 30 ° elbows are designed for detour and turns in difficult terrain.

If the track length is more than 15 meters, a revision insert is installed. An inspection well is equipped to access the revision.

After laying the pipes and putting them into the sewer well, the correctness of the slope is checked, and the trench is covered with soil. The soil around the pipe is compacted, large stones are removed and clods are broken.

Plastic pipes for outdoor sewerage are usually painted orange. In areas with deep soil freezing, insulation is used for sewer pipes.

Internal plumbing and connection to the central pipe

Two 45 ° elbows are connected to the socket of the external sewage system introduced into the house. The result is a 90 ° angle, directed vertically, to the bell of which a central riser with a fan pipe is mounted.

The waste pipe is a continuation of the riser and is brought out to the roof of the house. It is connected to the riser, having previously equipped with a revision. The waste pipe is required for the operation of a sewerage system equipped with a septic tank. It is unacceptable to combine the fan pipe with an exhaust hood or chimney.

1 – sewer well; 2 – drainage pipe; 3 – bends 45 °; 4 – connection for the toilet; 5 – sink connection; 6 – revision; 7 – fan pipe

Plumbing objects connected to internal wiring include:

• kitchen sink;
• dishwasher and washing machine;
• sink;
• bath;
• shower cabin;
• toilet bowl;
• bidet;
• ladder.

Plumbing is equipped with siphons and is connected to an internal wiring pipe. A shaped tee with an outlet of the corresponding diameter is installed at the connection point. For the correct installation of the internal sewer wiring, some rules must be observed:

1. Internal wiring is mounted from a pipe with a diameter of 50 mm. To connect plumbing fittings, shaped tees with outlets of 50 or 40 mm are inserted.
2. The slope of the pipe is 2 cm per 1 linear meter of the wiring. The plastic pipe can be easily cut with a hacksaw for metal. To begin with, a measurement is made without an O-ring rubber. The pipe is cut to size. The pipe cut is cleaned with sandpaper and lubricated with waterproof silicone.
3. To eliminate blockages, the pipes are equipped with a shaped oblique tee with a plug.
4. The toilet is installed in the immediate vicinity of the riser, within 1 meter, and is connected to the riser by a 100 mm pipe.
5. Clamps are used to fasten the sewer pipes. Clamps are installed in 70-100 cm increments.

After completion of the installation, the sewerage system is checked for sealing. Attention is drawn to the joints and the installation of fittings. If a leak is detected, the unit is disassembled, wiped dry, treated with sanitary silicone and assembled again.