Do-it-yourself replacement of sewer pipes in an apartment

Stages of preparatory work

As with any housework, replacing old sewer pipes will be faster and more efficient if the work is assessed in advance, planned and carefully prepared. The whole volume can be divided into several stages.

Planning and purchasing materials

Due to the fact that in this case there will be no installation of sewage from scratch, but only the replacement of pipes, design work can be simplified. However, they must be carried out in two cases:

it is planned to change the scheme of the engineering system, taking into account the shortcomings of the previous version;
you need to add new consumers.

If the system functioned successfully, experts recommend laying pipes along the old route and using existing technological holes in the partitions.

Before replacing a sewer pipe, it is necessary to clarify the number and nature of water intake points in an apartment or house. They are: household appliances, namely washing and dishwashers, sinks, toilets, bidets and others.

In this case, it is easier to purchase materials. When compiling a shopping list in a building materials store, you will also need to measure the old pipeline and census of the fittings used. Naturally, new sewer pipes and fittings will be qualitatively different than those dismantled, as their production industry is rapidly developing, offering more and more effective solutions, but quantitatively the volume will be similar. It is only necessary to provide a certain margin.

Pipe measurements

Today, polymer pipes are mainly used for sewerage installation, steel pipes are less common, the installation of which is associated with certain difficulties.

Dismantling

When the old system has been studied, and the places that need to be changed have been clarified, you can begin to dismantle it. Basic rules for dismantling:

It begins with the fact that furniture and household appliances that can interfere and are subject to the possibility of being damaged are taken out of the room.
First turn off the water supply, also disconnect the hose that leads to the toilet flush tank.
Old sewer pipes are cut into fragments with a grinder and taken out of an apartment or house.
If the place where the pipe runs is far from the riser, and you can’t crawl there with a grinder, you can simply break it with a hammer or sledgehammer, since the cast iron is quite brittle.

Sewer dismantling

Installation of internal wiring

After the installation of the riser, it is necessary to change the internal wiring in the apartment. The work rules include the following recommendations:

Wiring is performed from the central riser to plumbing fixtures (toilet, sink).
It is necessary to install not only rigid, but also movable elements of the pipeline. The movable elements made of corrugated pipe relieve the internal stress of the system.
The sockets should be positioned towards the movement of waste water, this reduces the risk of leakage.
Sewerage should be installed with a slope towards the drainage.
To drain water from the toilet, a pipe with a diameter of 110 mm is used.
For all other plumbing fixtures, a 50 mm piping must be used.

After the installation of the wastewater disposal system, the drain tank is connected and a test run is performed. The correct operation of the cistern depends on the proper connection to the toilet and the tightness of the connection with the supply pipe. There are also models of a cistern that must be fixed to the wall. All the necessary accessories for installation, as a rule, are supplied with the equipment.Also, the cistern device can be hidden inside the plasterboard structure, which will add aesthetics to the restroom.

Compliance with simple recommendations for laying a network for drainage guarantees the reliable functioning of all plumbing fixtures in the apartment, the absence of leaks, extraneous noise and odors. If there are difficulties in carrying out the work on your own, you can call qualified specialists.

How to dismantle a cast iron pipe

If the pipe is “welded” to the wall or floor with sulfur or aluminum, it will be very, very difficult to destroy such a coating.

To get started, you must first turn off the water supply to the apartment. Then you need to free the bathroom from unnecessary items that you can damage during work. This includes a sink, washing machine, laundry basket, and more.

Next, you need to disconnect the drain tank from the water supply and dismantle the toilet bowl itself. Problems can also arise here, since Soviet toilets were screwed to the floor to the conscience, in other words, tightly.

Try to unscrew the bolts that attach the toilet to the floor and remove it from its place. If you succeed, consider yourself half done.

Now comes the turn of the pipes themselves. Cast iron, as you know, does not differ in particular strength, therefore, at some distance from the riser, you can simply break the old pipe with a hammer. It is much more difficult to remove the remnants of pipes from the old riser and clean them before installing new ones.

To dismantle pipes, you may need:

Hammer with rubber or plastic tip.
Chisel
Burner or blowtorch
Mask

Quite a strange combination, isn't it? However, a gas mask is necessary to comply with safety regulations if the joints of the sewer pipes in your bathroom are filled with sulfur.

The easiest way to remove sulfur is to heat it. However, when heated, the sulfur mass releases toxic substances into the air, which are extremely harmful to a person inhaling. That is why it is better to protect yourself in advance with a gas mask.

So, dismantling must begin at the place of greatest distance from the riser. Here, most craftsmen do not suffer with a burner, but simply break the pipe with a hammer. This is much easier, but can cause some complications.

Make sure that pieces of pipe do not fall into the sewer passage when broken. They can cause a serious blockage in the sewer, which will be much more difficult to get rid of than getting rid of old pipes.

With a hammer, you can destroy the pipe to the very cross, inserted into the riser. Here it is somewhat different and filled with gray much more.

To free the pipe and cross from the layer of sulfur, you need to heat it. The impact of a burner or a blowtorch can last for several hours, while harmful substances will be constantly released.

Before starting heating, isolate animals and households, cover furniture or other furnishings in the immediate vicinity of the riser, put on a gas mask.

During the heating process, you can easily chip off lumps of sulfur until the pipe is sufficiently clean. Now, the cross, inserted into the riser, must, if possible, be loosened and removed from the riser.

The dismantling of the old pipeline is carried out to the maximum. That is, pipes are removed as much as possible, and others are mounted in their place.

Connecting a new PVC pipe to an old cast iron riser will require some skill to work with. Please note that you must clean the junction as much as possible from the same sulfur and rust.

To facilitate the work, use a special coupling, which is specially designed for connecting cast iron pipe and PVC pipe.

If you have any questions, take a look at ours and ask them there. Our experts will help you understand the intricacies of good construction and repair.

From time to time, the pipeline wears out under the influence of mechanical stress and it is necessary to replace the sewer pipes in the apartment. Most often, residents of old houses face such a problem, where over the years cast-iron pipes rust, cracks appear and leaks occur.

To change the drain lines, you must first properly dismantle the old pipes. Successful completion of the task requires the availability of appropriate plumbing tools and the necessary components.

Removing the cast iron pipe

The dismantling of the riser begins with the removal, located between the tee and the ceiling. First, an annular gap is made on top of the section. To do this, at a distance of 12-16 cm from the ceiling, using a grinder, a cut is made in the pipe with the rest of the wall of about 3-5 cm.

An incomplete cut is needed to prevent jamming of the tool with a possible vertical movement of the column. Then, stepping back 9-13 cm down, a similar cut is made, parallel to the first. The ring between the cuts is carefully knocked out with a hammer or wedges.

The next step is sawing the cast iron section from the bottom. For its implementation, an incomplete cut by a grinder is made at a height of 50-70 cm from the upper socket of the tee. The clamps securing the section to the wall are removed (they can simply be cut off with a grinder). The pipe is broken by swinging or hitting with a hammer at the place of incomplete cut and removed from the column.

Tee dismantling

The most important operation of the entire dismantling of the old sewage system is the removal of the tee from the socket of the lower section of the riser

As noted, there is an important condition: this bell must not be damaged. The simplest dismantling options are used when filling the junction with cement mortar

First, an attempt is made to separate by loosening.

A crowbar is placed in the hole of the rest of the pipe, with its help bending forces are created in different directions. Most often, such loosening destroys the cement bond, and the tee can be removed from the lower socket. When the joint is destroyed, the ingress of large cement pieces into the pipe should be eliminated, that is, the cement is removed from the socket with a screwdriver or chisel.

If loosening did not lead to a positive result, then a more time-consuming method will have to be applied: the cement mass is destroyed with a chisel and a hammer

Given the brittleness of cast iron, this procedure should be carried out very carefully, and the impact force should be applied away from the walls of the socket. The goal is to provide a gap between the tee pipe and the socket walls

As the cement pieces break off, they are immediately removed from the joint area.

The most difficult method of dismantling has to be used when filling the joint with sulfur. Such a composition is very durable and does not lend itself to the destruction methods described above. In this case, heating of the joint area is most often used with a gas burner or a blowtorch. The work is carried out by two people. One worker warms up the joint, and the other loosens the tee.

When the mass is melted, the tee is easily removed from the socket

Such work takes place when very harmful gases are released, which means that precautions must be taken (respirator and goggles)

Finally, extreme circumstances may arise when it is not possible to remove the tee from the lower section in any way (it is impossible to use heating, especially strong pouring and other non-standard situations). In this case, the most undesirable option is used - the tee is cut off at a height of about 5-6 cm from the socket. The end of the rest of the pipe is carefully aligned, and subsequently, when installing plastic pipes, you will have to use a coupling.

If the installation of new plastic sewer pipes is planned, then it is impossible to do without the rather laborious dismantling of the old cast-iron sewer.This process can cause a number of difficulties, so you should prepare in advance to solve problems that arise.

When replacing a worn-out pipeline, the most difficult task is to dismantle the cast-iron pipe. The material with which the pipes were connected adds to the complexity of the work. Previously, cement mortar, sulfur or aluminum were taken for reliable pipe joining (see. Thus, the whole structure became almost monolithic. It is quite easy to remove the cement composition, but sulfur and aluminum are forced to make maximum efforts (see).

Dismantling of worn-out elements of the sewer line

In order to repair the sewer in the apartment, it is necessary first of all to identify the location of wear. If there is major damage to the outlet lines, it is enough to simply turn off the water supply in the apartment, remove the plumbing fixtures and proceed to remove the worn area. If a sewer riser needs to be replaced, it is necessary to coordinate your actions with your neighbors in advance, because the water supply will have to be shut off for them too. It is difficult to calculate the exact time how much sewer pipes will be repaired in advance. However, proper preparation and adherence to the planned plan guarantee the successful completion of the process.

Removal of damaged sewer sections consists of the following steps:

Shutting off the water supply to the apartment or to the entire riser.
Switch off the cistern device in the toilet. To carry out the dismantling of the cistern, it is necessary to disconnect the water supply hose.
Removing the toilet. The process is quite laborious, you will need to free the base of the toilet. Sometimes it is enough just to unscrew the bolts, but sometimes you have to remove a layer of tiles around the toilet leg. The toilet bowl must be dismantled using a special tool: a wrench, a chisel, a hammer.
Dismantling of the sewer system. Old pipes cannot be reused, so they can be dismantled using physical force and a hammer without regret.
If the replacement of sewer pipes will be carried out only in your apartment, the next step will be to cut the riser with a grinder.
The incised pipe should be carefully removed with a hammer and chisel.
You can try to remove the lower part of the drainage system near the riser by simply swinging it to the sides. If this manipulation does not lead to the desired result, you will need to make incisions with a grinder

How many cuts to make on the pipe is not so important. The main thing is to achieve its split in order to further remove individual fragments.
Clean the socket from grease, cement residues and other contaminants, prepare for installation.

Calculation of the sewer pipeline

The choice of material for sewer pipes

Of all the possible types of sewer pipes for do-it-yourself repairs, pipes made of polymers are chosen.

Advantages of plastic pipes:

Corrosion resistance.
Chemical resistance.
Easy assembly.
Light weight.
Smooth wall surface (internal).
Resistance to low and high temperatures.
Ease of repair.
Durability.

Compared to metal pipes, plastic products are more fragile, so care must be taken when handling and storing. This disadvantage is compensated by light weight and ease of installation.

Choosing the diameter of the sewer pipe

Minimum allowable diameters:

Bidet, washbasin, sink - 40 mm.
Shower cubicle, bathtub - 50 mm.
In the case of including several plumbing fixtures in one pipe - 85 mm.
Riser (main) of a house or apartment - 100 mm.

The versatility of the system can be achieved by using a 50 mm diameter pipe to connect all plumbing fixtures, except for the toilet bowl, and make the main riser from a 110 mm diameter pipe, connect the toilet bowl to the same 110 mm sewer pipe.

Calculation of the number of system elements

To calculate the pipeline and carry out the installation of sewer pipes, it is necessary to draw up a diagram of the future system. It is enough just to take a sheet of paper and place on it all the plumbing fixtures that need to be connected.

Approximate scheme of the intra-house pipeline

It should be noted that it is not recommended to use bends with an angle of 90o. In this case, it is better to use two 45° bends, which significantly reduces the likelihood of blockage in the pipe.

A wide range of fittings - angles, crosses, tees, couplings - will allow you to choose the necessary element of the desired configuration and the required diameter. If you plan to install another plumbing fixture in the future, then determine the installation location and add it to the diagram. During installation of the system, this outlet will be closed with a plug until it is needed.

Having selected all the necessary pipes and fittings according to the scheme of the future pipeline, you can proceed to the next stage of the repair.

Sequence of work

Some may think that dismantling old communications can be done quickly and without problems. However, it must be borne in mind that the riser passes through several apartments, which means that in the event of a breakdown, many people will suffer. Dismantling is a plumbing work of increased complexity. Requires some experience with tools and equipment, compliance with safety measures. Therefore, such a responsible work should be entrusted to qualified specialists.

To completely eliminate possible emergency situations, you must perform the following manipulations:

shutdown of water flowing through the riser;
disconnecting a hose that goes directly to the toilet;
dismantling the toilet bowl, for which the fixing bolts are unscrewed;
all unnecessary materials, equipment, household appliances and plumbing are taken out of the room so that there are no unnecessary barriers for dismantling;
pipes located a little further from the riser are dismantled with a hammer;
get rid of the structures leading to the riser;
a special cuff is installed on the socket of the tee, for which old lubricants are removed in advance. If this is not done, then it is impossible to talk about the quality installation of the new system.

Important! Inaccurate installation of the collar can damage the tee. In such a situation, it will be necessary to replace a certain section of the riser, which will entail additional costs.

Dismantling guide

Due to the fact that the sulfur that connects the communication sections tends to harden, demolition will be difficult. So how can you understand what composition was used for fastening? To find out, you need to bring a blowtorch to the connection. An unpleasant odor and melting indicate the presence of sulfur.

Dismantling joints with a burner or blowtorch

To destroy the pipeline, where there is a connection using sulfur, you will need a hammer, chisel, blowtorch or burner. Sulfur is a chemical element, therefore, when heated, it will release harmful substances into the air. They are poisonous to humans and harm the environment. Moreover, the heating process can last several hours. Therefore, a gas mask and other protective equipment will be required to prevent the fire of nearby equipment or furniture. You can use a protective screen made of a metal base or asbestos.

Detailed instructions for dismantling communications

The dismantling of the system begins with the elimination of pipes located at a distance from the riser. For operational work, a hammer and a chisel are used. After all, cast iron itself is a rather brittle material, respectively, it is easily amenable to mechanical destruction.

Important! To disassemble pipes, it is not recommended to use a hammer with a metal nozzle.If you do not calculate the force of impact, the hammer will fall into the pipe, which may cause a large-scale blockage of the sewer system or close the gap of the pipeline

For work, a hammer with a polymer nozzle is suitable.

The process of removing the pipe includes several stages:

1. Work with a hammer is carried out until the cross in the riser becomes visible.

2. It is necessary to loosen the cross. This procedure is easier to do when a small section of pipe remains. However, some masters do not leave too much to fully open the connection.

Put on all protective equipment, take precautions through protective screens. If two professionals are involved in the dismantling, the work will take less effort and time.

One specialist heats the sulfur, the second, at the same time, loosens the pipe, cleaves and removes the viscous sulfur.

4. The cross is easily removed from the riser when most of the sulfur has been removed.

Important! Care must be taken when removing a pipe bonded to a tee. Part of the pipe is cut off with a grinder. In this case, a fragment with a length of no more than 10 cm should remain.

Then this segment must be loosened and removed.

In this case, a fragment with a length of no more than 10 cm should remain. Then this segment must be loosened and removed.

Carrying out work

The dismantling of the old sewage system includes several main stages: dismantling the intra-apartment piping, removing the cast-iron riser pipes and dismantling the tee (cross).

Removing the apartment system

When carrying out a major overhaul, it is advisable to completely disassemble the wiring (to the kitchen and other devices). If the joints are made very firmly, then it makes no sense to waste time disconnecting all the elements.

It is simply cut as close as possible to the socket of the outflow of the tee using a pipe cutter or grinder. Difficulties with disassembly may arise if the pipes were previously masked by floor coverings - they will have to be carefully removed. Even worse, if the pipes got under the concrete floor screed. In this case, you will have to work with a puncher, a chisel (chisel) and a hammer.

Dismantling of the old sewerage system

The dismantling of sewer pipes begins with the preparation of the premises. It is necessary to free the workplace from all unnecessary things in order to gain full access to the riser and sewer pipes. You also need to prepare a tool for work: a hacksaw for metal, a grinder, a set of screwdrivers, a hammer, a puncher, a chisel, a needle file.

Dismantling steps

If you are making repairs in a multi-storey building, then you need to agree with your neighbors in the sewer riser that at such and such a time they will not use the sewer. Otherwise, all the drains will be in your workplace.
Turn off the water.
Disconnect the water supply hose to the drain tank.
Remove the toilet by first unscrewing the bolts securing it to the floor.
Disassemble and dismantle old pipes.

Disassembly of cast iron pipes

Since the old sewer system is made of cast iron pipes and socket fittings, dismantling is not difficult. The pipes must be pulled out of the sockets using auxiliary tools - a chisel and a screwdriver. If the junction cannot be disassembled, then it is worth using a grinder or a hacksaw

By making cuts in the necessary places and gently hitting with a hammer, you can remove part of the system

Particular attention should be paid to work at the junction with the main riser. You can’t use a hammer here, as you can violate the integrity of the entire house sewer system

The tee connected to the riser is carefully cleaned of the remnants of the old seal. If, during disassembly, it was not possible to pull the pipe completely out of the joint with the riser, then using a grinder with a small circle (the diameter of the cutting circle should allow you to enter inside the tee), cut the rest of the pipe into pieces and pull them out with a chisel.If necessary, you can use a puncher with a drill for metal.

Pipe replacement

It begins with changing the siphons located under the sinks, after which you can determine the amount of slope. Installation of pipes is carried out from the riser, the diameter of the pipes decreases with distance from it, which is associated with a change in the number of drains and the load on the system. The exception is the pipe leading to the toilet, regardless of how far it is from the riser, for this role a product with a diameter of at least 100 mm is selected.

Siphon replacement

If the movement of drains is carried out under the influence of gravity, it is necessary to observe the slope. Otherwise, there will be frequent blockages in the sewer.

It happens that the natural movement of wastewater is impossible, then a fecal pump is included in the system, which is required to pump out waste, and in such a situation a slope is not necessary.

The connection of pipes is carried out by inserting the end of one pipe into the socket of the other. This type of connection is quite simple. To guarantee the tightness of the connection, a special gasket is inserted into the socket, which ensures a snug fit, and insurance in the form of the use of silicone sealant will not interfere in this matter, it is recommended to use it in any type of joints

When installing pipes, special attention should be paid to the quality of the connections, including and in those places where the diameter of the pipe changes

The work in the area of the plastic sewer riser also deserves special attention: before changing the sewer pipe that fits it, it should be fixed so that the dismantling work does not damage its integrity. If this procedure is neglected, the riser may loosen and burst from an increased level of vibration.

Fixing the riser

Replacing sewer pipes is not an easy and responsible process, but if appropriate preparation is carried out, and replacement actions are carried out exactly according to the instructions, the result will be simply excellent.