Sound insulation of sewer riser: review of materials, techniques, installation

The modern market of building materials for performing work to reduce the sound level in the house is presented in a wide range. Let's consider how sound insulation of a sewer riser is created. Let's get acquainted with the reasons for the spread of noise and the materials used to eliminate them. Read to the end and you will learn how installation work is carried out sequentially, what should be taken into account.

Cast iron sewer riser Source oboiman.ru

Noises and reasons for their appearance

Sources of sounds in a residential area can be nature, transport, operating equipment, the operation of utilities, and even the steps of neighbors. For humans, sound intensity indicators are important. Sanitary standards are set out in SanPiN 2.1.2.2645 of 2010 (in a living room, 30 dB is allowed at night and 40 dB during the day). Examples of indicators that are typical for everyday life (in dB):

0 – lower threshold, which is perceived by the hearing organs;
up to 30 – natural noise level in nature, human whisper;
up to 40 – normal sound level for active life, but not for sleep or rest;
within 60 – an area with busy traffic, active communication within a distance of 1 meter;
100 – inside an industrial enterprise, a forge shop, in a concert hall (for example, rock music);
130 is the sound level that causes pain.

Measuring the noise level at an enterprise Source wp.com
For the installation of a sewer riser, pipes of a wide diameter are used (today it is 100-110 mm). In such a channel, both liquid and solid waste move freely. This is often accompanied by noise. Upon closer examination, the reasons for soundproofing a sewer riser are:

Impact load on internal walls. This is observed to a greater extent at the junctions, turns and branches of the highway.
Collision of different flows. A similar phenomenon occurs in multi-storey and apartment buildings. Here, different waste streams flow simultaneously from different points.
Installation errors. More often, noise arises from impacts of the channel against ceilings, incorrectly selected fasteners, and elements of the cladding structure. The reason is vibration of the pipes during operation due to unreliable fixation. Otherwise, the phenomenon is called resonant or structural noise.
Selection of fan pipes. The modern market is filled with ready-made solutions, but cheap products including fasteners are often installed. In particular, they choose plastic with thin walls and plumbing clamps that quickly weaken.

An ordinary thin-walled plastic pipe Source dostavkin.com
It is believed that infrasonic waves are the most harmful to humans. This phenomenon is unsafe and is not perceived by the auditory organs. It occurs in a building due to the vibration load of fan pipes on floor slabs and walls at contact points and through fasteners.

Why does plastic make noise?

Researchers find several sources of noise in the pipe:

Impact - when the contents fall in the riser, they hit the walls.
Atmospheric - simply the noise of the wind in a ventilated riser.
Resonant – extraneous sounds are heard in the pipe.
Vibration – vibrations of the building are transmitted to the pipe, etc.

Why is the trumpet so sensitive to sounds? Because it is a pipe, an acoustic resonance system, and, unlike an organ or wind pipe, it is multi-frequency. The length of sewer risers from bottom to top is from several meters to tens of meters; speed of sound in air – 330 m/s. The main resonant frequency of the riser will be from several hertz to tens of hertz, and the overtones will be located on the sound frequency scale at intervals equal to the fundamental frequency. That is, with the slightest periodic impact on the pipe, it will give an almost continuous hum: in the region of best audibility, the untrained human ear can no longer distinguish a frequency difference of 20 Hz.

Resonance phenomena in a pipe cause not only vibration of its walls, but also alternating deformations (bending, tension/compression) of the pipe body, i.e. pipes in general. The sound from the vibration of the walls is transmitted directly to the rooms, and alternating deformations, in addition, affect the structure of the building.

Soundproofing methods

Materials and techniques are used to prevent and eliminate the causes of various types of noise and sound waves. Only old-style cast iron channels do not need this. They themselves are thick, the alloy has the property of reducing the amplitude of sound wave vibrations. Additionally, this is facilitated by plaque with growths on the inner walls.

In the case of plastic analogues, the following decisions are made:

artificial increase in the total mass of the pipeline;
use of soundproofing materials or installation of insulating engineering structures;
installation of special clamps with rubber gaskets (damping).

A universal option can be considered replacing a thin-walled plastic fan pipe with a modern sound-proofing analogue.

Structure of a three-layer silent pipe Source edilportale.com

The sought-after sample consists of three layers:

internal – smooth polypropylene pipe with high wear resistance;
medium - a mixture of polypropylene and stone flour or carbonate chips to make products heavier and reduce vibrations of sound waves and vibrations;
outer – high-strength polypropylene, which is characterized by rigidity and resistance to impact loads.

The third problem area is the point of contact between the channel and the floor slab. Here, sound insulation of the sewer riser is performed using a damper insert. These can be special rubber rings or pieces of shell-type pipe sound insulation.

See also: Catalog of companies that specialize in water supply, sewerage and related work

Most common mistakes

There are cases when, after carrying out soundproofing work, the desired effect is not achieved. This happens due to mistakes made. Let's look at them:

Incorrect choice of sound absorber. This choice includes mineral wool or mounting Mineral wool is an excellent material intended for insulation, but it is not very suitable for isolating noisy sounds.
It may be that the soundproofing material does not lie tightly on the sewer pipeline.
During installation of the riser, a rubber sealing gasket is not installed.
Rubber gaskets are not used when attaching clamps to the wall.

In order to get rid of the noise of sewer pipes, it is necessary to use the most modern soundproofing materials. Such modern materials are foamed polyethylene, porous rubber and others. Reducing noisy sounds will help you achieve comfort and coziness in your living space. You are required to spend your time on this work.

Overview of materials used

Sound insulation for sewer pipes is represented by various materials in composition and technical design. These can be sheets, rolls, ready-made hard or soft products in the shape of a cylinder. On trading platforms, suitable samples look like this:

foamed polyethylene or polystyrene for covering pipes of one diameter or another;
polyurethane foam in the form of a hard shell;
foam rubber products;
damper tape in various designs;
automotive vibration isolation.

Vibration-isolating material Source lamptochka.ru
The main characteristic of sound insulation for sewer pipes is the strength of sound that it can absorb. In fact, the stated indicators, as a rule, correspond to the real ones. However, experts recommend considering options with a margin of 15-20%.

Application of roll materials

It is recommended to choose a canvas based on two criteria: noise absorption coefficient and the nature of the base. The best material is considered to be the one whose base is more rigid and durable. It will last longer, which is justified by the long-term preservation of integrity and a given shape under the influence of operating conditions.

The procedure for carrying out installation work is as follows:

the drainage channel is treated with a degreaser;
a piece of canvas is pre-measured and formed;
using a roller, air is eliminated between the sewer pipe and the sound insulation;
Using plastic ties, insulated or steel binding wire, plumbing clamps in the form of a ring with a screw or a harness, the material is fixed (the thinner the fan channel, the more often the fastenings are located).

Sound insulation screed in various ways Source yandex.net
There are slight differences in how the selected sheet is initially attached. The insulation can be made with an adhesive composition already applied. Such a sample must be distributed carefully over the surface of the pipe to prevent the formation of bubbles.

The remaining blanks are attached to pre-evenly applied glue or silicone mass. Here there is little time to adjust the position of the sound insulation. Excess is eliminated if it has a negative impact on the overall appearance of the work done.

In both cases, it is recommended to form a slight overlap. This will ensure that the entire surface of the sewer drain is covered. The main thing is to securely fix the outer edge to prevent its movement, which provokes the appearance of structural noise.

Rolled sound insulation for pipes Source akustika63.ru

Soundproofing the riser of the main source of hum

Very often, third-party loud sounds and vibrations come from the riser. It is through this that drains from all apartments pass. Therefore, soundproofing a sewer riser with your own hands must be done carefully and competently. We will explain the entire execution algorithm.

The riser is very often considered a source of foreign sounds and vibrations

Do-it-yourself sewer soundproofing

First of all, you need to select a soundproofing material (depending on the coatings recommended above). Cut it to the size of the riser. The insulator must completely bend around the main sewer pipe. If roll-type products are used, they must overlap the riser. After installing the soundproofing, first secure it with construction tape. Materials in rolls, as noted, are secured with a specialized aluminum tape. It is recommended to additionally secure the polyethylene foam with plastic fasteners or tie it tightly with thin but strong wire. When installing fasteners, maintain a distance of 0.25 m between them.

As a rule, at this point the noise protection of the riser can be considered complete. However, if the area of your bathroom is very large, it makes sense to hide the pipe in insulation so that it does not spoil the interior with its unattractive appearance. This can be done using plastic wall panels or by improving the plasterboard box. The last of these structures will provide additional protection against noise.

The box is installed like this:

Mark the dimensions of the masking structure on the surface of the walls. Decisive moment. The walls of the box should be 55–60 mm away from the riser.
Using dowels or screws, install metal profiles in selected areas.
Fix another profile product from the wall surface to the floor surface. The location of its placement is determined by the intersection of lines drawn perpendicular to the two previously installed profiles.
Place the jumpers (the distance between them is about half a meter) on the metal frame.
Screw the gypsum board sheets to the completed skeleton. Advice. Buy products that are moisture resistant. For use in plumbing units, they are better than the usual gypsum properties and thickness. Don't forget to cut out a small window. It will act as an inspection hatch.

The space between the riser and the box can be filled with mineral wool. But do not forget that it will play the role of insulation. Mineral wool does not protect against foreign sounds. The ideal option is to fill empty spaces with the same polyethylene foam. Soundproofing costs will increase in this case. But the effect from them will be impressive. Unpleasant sounds from sewer pipes will no longer bother you and your family members!

Thematic publications:

Installing a shower tray with your own hands - the main methods

Installing a sink - good DIY installation

Clearing a sewer in a privatized house - how to remove a blockage at home

Video description

This video shows in detail how to assemble a plasterboard box and insulate a sewer riser with mineral wool:

Fastening the shell

Rigid ready-made materials for soundproofing sewer risers are easy to use. These are sleeves that are made with mounting longitudinal edges for reliable and tight fixation. After additional fixation of the casing with clamps or ties, a monolithic shell is obtained. The main thing is to maintain the diameter of the fan pipe and shell. They must be identical.

"Silent" pipes

This is perhaps the most reliable and modern method of removing noise from the sewer system, but it is only available at the stage of installing a drainage system or its major repair. Moreover, when installing sewerage systems in apartment buildings, such a system is effective only if it is used on at least two or three adjacent floors.

The principle of “silent” pipes is the use of a multilayer structure of the pipe itself plus special noise-absorbing fasteners.

In our country, the Rehau Raupiano system is quite widely represented, which includes a wide variety of pipes of different diameters, lengths and purposes, connections for them and fastenings.

There are also Ostendorf, Waving and Politek (Russia) systems.

With the help of such “silent” products, home communications can be completely formed, as shown in the diagram below.

You can learn more about the features of pipe communications from the Rehau company from a video recording of a seminar dedicated specifically to silent sewerage.

Video description

The video shows the principle of installing silent pipes using the example of products from FORUMHOUSE:

Mounts and rings

Damping structural elements are made of elastic and durable rubber. These are seamless cylinders, linings, sealing strips. Alternatively, the former can be replaced by sections of a rigid casing.

Clamp with a rubber seal for fastening the pipe Source arsenal007.ru

The master’s task is to soundproof sewer pipes by rigidly fixing them. In ceilings, the opening is additionally filled with plaster mortar, which gives minimal shrinkage as it dries. Polyurethane foam or adhesive foam can also be used. The fastener is used in the form of a clamp with a threaded rod. She sinks into a dowel in the wall.

How to get rid of unnecessary sounds and vibrations in the bathroom: step-by-step instructions

Before starting work, you need to eliminate leaks, if any, and also clean the pipes from dust and dirt. To prevent condensation from forming, the water must be turned off.

Ideally, the sewer riser should pass through a sleeve in the ceiling filled with soundproofing padding. But in old buildings this standard is not met, so sound insulation is installed locally:

the hole around the pipe is cleared;
the base is wrapped in fiberglass or asbestos fabric;
a section of the floor (or ceiling) is filled with mortar and leveled.

It is not recommended to use polyurethane foam for sound insulation. It has good thermal insulation, but does not protect against noise.

Next, you need to cut the insulation into pieces of suitable size. Wrap the material around the pipe and secure it in any convenient way. The fit should be as tight as possible. Fill the joints with glue or resin. If the instructions for the material contain appropriate recommendations, then lubricate the pipe itself and the insulation surface with glue. After 15-20 minutes, apply it to the riser, seal the joints with tape or tape. Tighten additionally with plastic clamps and cut off the tails.

Recommendations from experts

When replacing a cast iron riser with a modern plastic one, you should not completely remove the old pipe. It is better to leave the crosspieces and areas that are located within the floor slabs. The next sequence of actions is as follows:

the middle part of the channel is dismantled using a grinder and a cutting wheel for metal;
the internal walls in the remaining pipes are cleaned of plaque and fat accumulations mechanically and chemically;
a plastic pipe is installed and secured using plumbing adapters and fasteners.

An example of a connection between cast iron and plastic pipes Source 4.bp.blogspot.com
In this case, noise insulation of pipes is carried out partially with entry into cast iron pipes. If you plan to replace the entire channel, then it is better to perform the task together with your neighbors. And in the ceilings a damper gasket is installed here.

Insulation materials are often mistakenly used to soundproof sewers. This is acceptable with mineral wool, but not with options such as polystyrene foam shells. Spraying polyurethane foam or polyurethane foam directly onto the fan pipe is also excluded.

There is an opinion that after completely wrapping the channel with a sound insulator, it is not necessary to use damping pads. They are necessary in any case. This eliminates the transmission of structural noise.

How to make a sewer box

To hide unsightly communications in the bathroom, you can use ready-made plumbing boxes. They are perforated U-shaped shells made of thin metal. They are most often used to disguise heating and plumbing, but can also be installed in the bathroom.

To install a factory box, you do not need to build a frame. There are fastening corners along the edges, which are screwed with self-tapping screws to the wall or glued with silicone glue.

Such structures have only one drawback - they do not have soundproofing properties. Therefore, the sewer pipe must already be wrapped in a membrane, mineral wool, or placed in a shell.

Additional sound insulation can be obtained by making the box yourself. The frame is constructed from wooden slats or metal profiles. The top is covered with plasterboard, wood, and plastic. If desired, you can place mineral wool inside.

To service the sewerage system, it is necessary to provide access to the inspection hatch. This can be done in ways:

provide a small door in the place where the audit is located;
install a removable wall in the box;
install sliding shutters.

If the sewer needs to be opened, it is enough to cut a hole in the soundproofing.

Increasingly, ready-made roller shutters are used to disguise pipes in the toilet. They are decorative and functional, easily opening to their full height. In addition, the installation aluminum profiles are filled with polyurethane foam, which improves the acoustic properties of the structures.