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15.2. Soundproofing. The principle of sound propagation.

Soundproofing of partitions. Soundproofing of floors.

Noise has harmful effects on a person, his body, nervous system, on general condition his health. Therefore, the interior of the building must be soundproofed. The source of noise may be outside the building, such as moving cars, inside the building, such as radios and televisions, or other types of noise.

Sound travels in any environment. If there is any obstacle on its way, for example a wall, then part of the sound is reflected from it, part passes through the wall, ceiling and floor, and part is absorbed (Fig. 398). Therefore, it is necessary to block the path of sound propagation in all directions.

Rice. 398.

1 - direction of the sound wave; 2 - reflected sound; 3 - sound penetrating the ceiling; 4 - absorbed sound; 5 - sound penetrating through masonry

It is known that soft and porous materials absorb sound more strongly than hard ones. Stone or iron are good sound dampeners when it is transferred from air to material. Light materials, on the contrary, transmit sound well when transmitting it from material to material. Therefore, it is better to alternate between hard and soft materials. Felt, jute, rubber, cork boards (such as damma, sordivit, empa, etc.), mineral wool mats, etc. are used for sound insulation.

Soundproofing of partitions. Lightweight double partitions have a middle layer, for example, in the form of multilayer slabs of roofing felt impregnated with bitumen mastic with one- or two-sided finishing with cork chips. First, one wall of the partition is erected and the slabs are glued tightly to it; the seams between them are covered with strips of bitumen cardboard 10 cm wide. Then another wall of the partition is erected.

If a double partition with an air gap is being erected, then the slabs are nailed to the first wall with nails with backing, and the seams are taped. The other wall of the partition is erected at a distance of 2-3 cm from the insulation. Air gap broken at a height of 75 cm with horizontal insulating strips 8-10 cm wide.

If mats made of mineral, basalt or glass wool are used as sound insulation, they are attached to the ceiling using slats and lowered to the floor. The seams are covered with bitumen cardboard. Then the second wall of the partition is erected.

Note. We should not forget about the need to isolate the partition from the floor, ceiling and side walls, otherwise sound will be transmitted through these structures.

Soundproofing of floors is carried out by using a heavy massive structure with light elastic insulating gaskets. Such a construction is, for example, reinforced concrete floor with sound-absorbing pads. Damma, sordinite, isoplat, empa, etc. slabs are used as elastic insulation. Elastic gaskets are laid directly on load-bearing structure and when erecting all types of walls, they are brought to the floor level (Fig. 399). The floor, including the baseboard, should not touch the wall to avoid the formation of a sound bridge.

Rice. 399.

1 - plaster; 2 - reinforced concrete slab; 3, 4 - insulation layers; 5 - roofing glassine; 6 - underlying concrete; 7 - concrete; 8 - clean plank floor; 9 - flashing; 10 - concrete strip

Device additional sound insulation by one-sided or two-sided cladding of partitions with an air insulating layer. Wooden plugs are hammered into the partition, to which planks measuring 2X5 cm are screwed at a distance of 50 cm (depending on the size of the slabs). Insulating pads are placed under the strips. Slabs 2.5 cm thick are attached to the slats. The seams between them are protected with bandages, on top of which a mesh is laid and covered with two layers of plaster. First layer - cement mortar, covering layer - lime-cement plaster. When using slabs of greater thickness, they are laid on a mortar. Between old partition and a new wall of insulating boards leaves a gap 3 cm wide, into which an insulating mat is placed (suspended from the partition) (Fig. 400).

Soundproofing the walls in the apartment. What to do and what not to do

Modern apartments far from ideal. How many times have you heard complaints about a neighbor who is too loud, a teenage pianist, and loud music at 2 am? All this can be solved, especially if you have just started renovation. Soundproofing – great solution for construction. A wide range of materials will allow you to choose the most suitable option for your home, and professionals in their field will perform high-quality soundproofing work.

What not to do

On modern market construction and finishing materials Today there is a huge selection of materials with excellent soundproofing values ​​and characteristics.

Very often, the buyer makes his choice based on precisely these parameters of the material positioned as a soundproofing material. But he does not take into account one very important circumstance. The values ​​indicated by the manufacturer show only the soundproofing characteristics of the material itself. And these parameters can manifest themselves only if correct application such material. The manufacturer cannot and should not take into account the ability of a sound wave to create vibration. This can and should be done by a specialist, at least at the level school education, familiar with the physics of sound.

Unfortunately, in our practice we often encounter the opposite. The most common mistake when soundproofing walls in an apartment is rigid binding of sound insulating material to the insulated wall. Beware and avoid sticking and fastening plastic dowels polystyrene foam or extruded polystyrene foam to the insulated wall. This is the most common incorrect way to soundproof walls. Your neighbor will thank you. He will absolutely not hear you. You will hear it twice as loud.

Avoid rigid mounting plasterboard construction to the insulated wall using regular dowel nails/screws. Get the opposite effect to what you expected.

These common mistakes are due to a basic ignorance of the properties of the sound wave. A sound wave passing through a solid barrier (in in this case through a wall adjacent to its neighbor) generates a transverse wave, causing bending vibrations of the obstacle. The sound simply shakes the wall. And the thinner and less dense the wall, the more it loosens. These vibrations create their own sound wave, copying the source acting on it. The thicker and more massive the wall, the greater its inertia, the weaker it will transmit sound. Easy soundproofing material rigidly attached to the main wall does not have sufficient mass to resist the bending vibrations caused by the sound wave. Sound insulation made in this way will not resist, but will only facilitate the passage of the sound wave, increasing the amplitude of bending vibrations.

How to do it

In what ways does sound enter the apartment?

1. By air

Sound can pass through walls where it encounters minimal resistance: through cracks in the wall, at the joints of wall and ceiling, wall and floor, wall and adjacent wall, through ventilation shafts, installation boxes of sockets and switches, through plastic window slopes, hollow window sills , through the windows themselves.

Getting rid of sound penetration by air is the simplest and most inexpensive option for soundproofing apartment walls. Simply plastering the walls is enough. If there are cracks, fill them with plaster to the maximum possible depth. Do not fill them with foam. Before applying plaster, it is necessary to carefully seal all joints around the perimeter of the walls with plaster or mineral wool. Make sure that your installation boxes do not coincide in location with your neighbor's boxes or install outdoor sockets and switches. Do not install plastic slopes filled with polyurethane foam. Polyurethane foam does not interfere with the penetration of noise from the street. Plaster window slopes. Install monolithic window sills (for example, stone ones). Install windows with double-glazed windows and different glass thicknesses. Such minimum set The measures taken will allow you to significantly get rid of unnecessary noise penetrating through the air.

2. Directly through the wall

This path has already been described above. Unfortunately, the thickness and massiveness of the adjacent walls in our apartments are not sufficient for good sound insulation interior spaces. Therefore, it is necessary to take additional measures to soundproof adjacent walls. The main thing is to avoid rigid connections between the soundproofing structure and the main wall.

This can be achieved by using special fasteners or a fastening system to secure the material, which allows you to secure the material in a vibration-decoupled (non-vibration-transmitting) way. Plus the installation of soundproofing gaskets around the perimeter of the soundproofing system, designed to perform the same task - not to transfer vibrations from adjacent walls, floors, and ceilings to the soundproofing structure.

3. Indirectly through floors, ceilings, communication systems, structural components of the building

A sound wave, having arisen in one room, transmits its vibration amplitude to the air surrounding it. Air environment in turn, transmits this amplitude to all solid bodies with which it comes into contact. These are both walls and interfloor ceilings, And various kinds nodes and communications of the building. This way, sound will travel not only through the adjacent wall, but also through adjacent walls, as well as the floor and ceiling.

To get rid of noise penetrating indirectly, sound insulation alone is not enough adjacent wall. In this case, you will have to go for a very financially expensive method of soundproofing an apartment - creating a “room within a room”. In other words, you need to soundproof absolutely all walls, ceiling and floor. This method is expensive and requires the involvement of those with certain knowledge. After all, it would be a shame to spend a lot of money and get “zilch” at the end.

Are you wondering what's happening on the other side of the wall? Are you interested in listening to this? It doesn't matter if it's a stranger or close person, whether it happens in your home or some other place, in any case, spying on another person is not very noble. If you do decide to eavesdrop, there are several ways to hear everything that is happening clearly and clearly. Be aware of all the risks and criminal liability before committing such an act.

Steps

Using a glass

Take a glass. So, you still decided to go for it. How to start spying? The most the easy way will attach the glass to the wall. An “acoustic connection” is created between the wall and the glass, which allows sound waves to travel from one side of the glass to the other. A soda or beer glass works best. Some spies claim that cardboard glasses are great for these purposes, but glass conducts vibration of sound waves much better than other materials.

Explore different parts of the wall to find the sweet spot. In some places on the wall the sound will be transmitted better. This occurs due to the uneven structure of the wall or due to different distances from the sound source. Check the sound quality in different points until you find best place. This can sometimes be difficult, especially if you need to listen through the ceiling. If you are too far from the wall, the sound will not be heard clearly enough.

Lean the edge of the glass against the wall. Remember that to achieve the acoustic effect you need to place the glass against the wall. Do this by placing the glass flat with the rim facing the wall. Now the acoustic waves travel from the wall to the glass, in the process the sound is amplified.

• Place the glass against the wall and place your ear against the bottom. Move the glass along the wall if the conversation is not clearly audible.

Using a hole

1. Make a small hole in the wall using a drill. Scientists have discovered this type of eavesdropping through walls using a hole and a plastic membrane. South Korea and Japan. First, drill a small through hole in the wall. Long and thin drill fits better everything.

   • Don't expect to hear too much through just one small hole. In fact, a single hole seriously interferes with sound transmission.
   • Try to drill a hole at the moment when your neighbor is also working with a drill. Otherwise, he may notice drilling debris and hear noise.

2. Cover the hole with a thin membrane. This will dramatically improve your hearing. Research shows that by covering the hole with a thin membrane, sound transmission improves so much that it appears as if there is no wall at all, since the membrane equalizes the pressure on both sides of the hole through which the sound passes.

   Eavesdrop. Once you have the hole covered plastic film, start listening! If you follow our instructions correctly, you will clearly hear everything that happens behind the wall.

   • For better effect you can combine this method with the first one. Place the glass over the hole with the membrane.
   • Remember that this method has its drawbacks. Your neighbor may hear a sound, notice a hole in the wall or debris left behind after drilling and become suspicious. Do everything very carefully!

With a spy stethoscope

1. Prepare the necessary components. Now we will use more specific spy equipment. You can make a stethoscope at home or buy one. The finished product will save you time, but you will have to spend several hundred dollars. A homemade stethoscope will cost you less than $25, but that's assuming you have a good MP3 player.

   Disassemble the microphone. You will need to open the microphone housing to get to the wires, then remove the cover and take out the microphones themselves. Then insert the removed microphones into the earphones of the stethoscope.

   • The most suitable tool for this is a utility knife. They can make an even cut that will allow you to get to the contents. You should have 2 microphones and a 3.5 mm plug (cable).

2. Disassemble and reassemble the stethoscope earpieces. Remove the headphones from the stethoscope. It's easy enough. They should come off with little effort. Don't throw away your headphones as you will need to install microphones in them.

3. Attach the stethoscope to your MP3 player. Finally, attach the stethoscope and microphones to the MP3 player. The sound coming from behind the wall will be amplified by microphones, transmitted to an MP3 player and recorded.

   • Connect the resulting stereo cable to your MP3 player. Your spy stethoscope is ready.

It has always been believed that my home is my fortress. However, there are moments when you are simply in own apartment impossible.

Many things can cause inconvenience: noisy renovation work in next door, very loud music and, of course, drunken brawls from above every night for a long period of time.

The noise that goes on around the clock, forces you to immediately look for at least some solution to eliminate it. However, not everyone knows how to overcome noisy neighbors.

The Federal Law states that the noise level should not exceed 40 dB between seven o'clock in the morning and eleven o'clock in the evening, but at night this figure should not exceed 30 dB.

If we take at least some comparison, then all sounds should be three times quieter than a car alarm. But still, do not forget that in each region amendments to this law can be made.

If the norms are violated by users of residential premises, all actions on the part of unscrupulous neighbors become an administrative violation.

However, it happens that while laws exist, they are unfortunately not implemented. In this case, there are a couple of options to solve the problem.

When very loud music is an obstacle, you can try to negotiate peacefully. This method is undoubtedly considered the best at that moment, if all participants in a given conflict are in an adequate state.

You can explain that you have a small child in your apartment and he needs to rest during the day, but in the evening he should go to bed at nine. You can compromise and understand each other.

In the event that peace negotiations do not go well, you can go to the local police officer, who is supposed to look into this situation at the request of the applicant. If there is a drunken brawl in a neighbor’s apartment, then it is best not to get involved in it, as there is a possibility of getting hurt. In this case, law enforcement agencies must intervene, who will immediately arrive at the scene when called and eliminate the conflict.

Neighbors are doing renovations

All repair work is a separate topic. When carrying out work using a drill, a person honestly thinks that he is not doing anything wrong, since it is working time, and therefore the law is not being violated.

But in some cases, this kind of noise can disturb an old woman who has a migraine and wake up small child. In this case, you cannot complain, since the law has not actually been broken.

If the person is well-mannered, then you can independently decide the time for him to spend the noisiest repair work, which will make it possible for this period of time to go for a walk with the child or not to go to bed at given time, but simply move it.

Request for help

So what should you do if the noise continues, but you can’t reach an agreement? It should be noted that the arrival of a district police officer often simply does not give the results that we would like. Very often, this moment depends on how rampant corruption is in a given area and, of course, on the identity of the offender.

In the event that the local police officer does not take any action on the application or nothing changes after his arrival, you should contact the prosecutor’s office directly, which monitors how the laws are observed. They must sort it out and the answer will come to you in writing.

If they didn’t help here either, then the only thing left is the court. If a claim is filed, there must be strong evidence that it is really impossible for you to relax in your apartment due to noisy neighbors.

How will the request to the housing office affect?

There is another authority to which you can file a complaint about particularly noisy upstairs neighbors who just want to annoy them. You should go there if there really are no illegal actions going on, which is rowdy behavior.

For example, a dog is constantly barking somewhere, or there is simply loud music from the upstairs neighbor. In these cases, it is permissible to contact the housing department. As a rule, employees of such an institution say that it is possible to conduct some kind of conversation, but it is not a fact that an apartment will be opened for them. So it's easier to call the police.

However, the police officers are not in a hurry to help, since their exit position is set up only for illegal actions, and loud music is the work of the housing department. And when the circle is closed, you should think about alternative methods.

There are exceptions

There are points in the silence law that may not be subject to time restrictions.

Items not included:

• A small sick child is crying;
• The cat meows or the dog barks;
• The church bells are ringing;
• Carrying out events and celebrations on the street;
• Rescue or emergency work accompanied by noise.

Consequences for violators

After the first warning has been issued and there is no effect, an administrative fine is then imposed. Its magnitude will depend only directly on who was the cause for concern - individual or legal.

The addition to the law states that those who like to place an amplifier on the balcony may also be subject to fines. The law has clear criteria for violating silence, for which you will have to pay a fine:

1. Construction and repair work at night;
2. Use of pyrotechnics and fireworks;
3. Listening to loud music when using amplifiers;
4. Whistling, loud screams and more.

Self help

In the event that no methods can help deal with noisy neighbors, you can simply make repairs using materials with enhanced soundproofing properties.

However, this is not always the solution. Yes, and the matter is quite troublesome. You can try using infrasound.

What is infrasound?

Infrasound is usually called elastic waves, which are analogues of sound waves, but have lower frequencies that humans cannot hear. The upper limit of the infrasound range is 16-25 Hz.

The lower limit has not yet been identified. In fact, infrasound is present in everything: in the atmosphere, in forests, and even in water.

Actions of infrasound

Infrasonic actions occur due to resonance, which is the frequency of vibration of a large number of processes in the body. Alpha, beta and delta brain rhythms also occur at the purity of infrasound, as, in principle, does the heartbeat.

Infrasonic vibrations can coincide with vibrations in the body. Subsequently, the latter intensify, due to which some organ malfunctions. It may not only lead to injury, but also to rupture.

The frequency of vibrations in the human body varies from 8 to 15 hertz. At a time when a person is exposed to sound radiation, all physical vibrations can resonate, but the amplitude of microconvulsions will increase many times.

Naturally, a person will not be able to understand the feeling of what is affecting, because the sound cannot be heard. However, there is a certain state of anxiety. If there is an extremely long and active impact of a special sound on the entire human organ, then ruptures of internal vessels, as well as capillaries, occur.

Typhoon, earthquake and volcanic eruption emit a frequency of 7-13 hertz, which gives a call to a person to quickly retreat from the place where disasters occur. Infrasound and ultrasound can very easily drive a person to suicide.

A very dangerous sound interval is the frequency of 6-9 hertz. Very strong psychotronic effects are most pronounced at a frequency of 7 hertz, which is similar to the natural vibration of the brain.

At such a moment, any work of a mental nature simply becomes impossible, since there is a feeling that the head could “burst like a watermelon” at any moment. If the impact is not strong, then the ears simply ring and a feeling of nausea appears, vision deteriorates and the person succumbs to unaccountable fear.

A sound that is of medium intensity can upset the digestive organs, the brain, cause paralysis, blindness and general weakness. Strong exposure damages or completely stops the heart.

Ultrasonic emitter

You can independently build an infrasound emitter that will not cause any harm to the human body, however, the unwanted neighborhood will become less noisy after its application.

Ultrasound design

The scheme is as follows: the simplest generator for creating oscillations is started from a coil, which is located in the speaker for sound. The relay is needed to start the capacitor. If you push the speaker to produce sound, it turns off completely.

Next, the circuit starts working on resonant frequency coils. We also need transistors that will be low-frequency and produce a certain sound power. A nine-volt power bank from a non-working modem is used as power supply.

Resistors R2 and R4 are volume controls. The circuit operates on a pendulum resonance. However, all the electrics take about two watts, but the output is about twenty, so the speaker does not work without them.

Any audio woofer will do. A prerequisite is to install it in a housing, since in this case the acoustic “ short circuit" The body shape is perfect for a saucepan. When using a jigsaw, the ears of the speaker for sound are cut off, then it is stuck into a bucket and glued together around the perimeter with a “moment”.

Setting up an infrasound device

Initially, the entire system is assembled on a table and all electrical components are checked. Initially, this must be done without a weighting agent. Once turned on, the speaker should begin to hum at its resonance frequency.

If it doesn’t work right away, you should work with the capacitance of the capacitor. Then the whole device is assembled into a pan, all the cracks between the speaker and the body are glued with a “moment”, and then the spiral of the weighting agent should be coated with glue and glued to the speaker diffuser for sound.

If it is not possible to find a normal purity meter, you should set the ultrasound frequency to 13 Hz using an oscilloscope and a low-frequency generator based on the Lissajous figure. Then turn on the power to test for a few seconds to see what happens. Next, the device turns off and begins cutting the weighting spiral until a double Lissajous is obtained.

One of important functions walls and ceilings is to block sounds. This is achieved in several ways. Ensuring the room is soundproof can be the same simple matter like sealing cracks around a door; however, it may require rebuilding the entire wall or lowering the ceiling. Noise not only travels through the air, but also easily penetrates through solids(through walls, studs and ceiling beams). Sound can also bend around corners and pass through very small cracks.

To create an effective sound barrier, the path through which sound travels through solids must be interrupted. Sound is the pulsating movement of air molecules through the eardrum. When a vibrating surface (such as a loudspeaker membrane or a person's vocal cords) disturbs the air in a room, it creates a wave-like movement of molecules. By colliding with each other, the displaced air molecules transmit acoustic energy (much like jelly transmits vibration) until the movement reaches the eardrums.

Any barrier that interferes with this movement weakens the sound; The denser the barrier, the less sound passes through it. Brick wall 100 mm thick is a significantly better sound barrier than a 100x50 mm wood-frame partition. Unfortunately, a solid wall with enough thickness to attenuate the sound significantly will be too heavy for the load-bearing floor.

Increasing the density of ordinary wood will not be of much help. frame wall due to additional layers of plasterboard or by placing insulating material between the studs - two common approaches to soundproofing. Often, the drywall continues to receive sound vibrations and transmits them through the solid studs, causing the same flexible drywall on the other side of the partition to move.

Acoustic tiles behave in a similar way - very effective at absorbing sound within a room, they do little to interfere with the transmission of sound from one room to another, since sound waves pass directly through their lightweight porous structure.

Two other factors complicate the soundproofing problem. The first of these, called lateral transfer, often occurs when neighboring houses are connected by a common wall. Although the noise may be partially blocked by a wall, the sound continues to travel through bypass paths (through open windows, for example) or transmitted in the form of vibrations through floors and ceilings. ъ

The second factor to keep in mind is the frequency of the sound you want to block. Providing soundproofing at the edges of the spectrum is a very difficult task.

An attempt to soundproof a home must begin by identifying obvious deficiencies in its protection. Repair common wall and repair any damaged connections. Extend the plaster closer to the floor if it is at the level of the baseboards. Fill the gaps around the ends beams, lying at the base of the wall, with mortar. Cover the areas through which pipes enter the room with acoustic seals or acrylic putty, electrical cables or other lines of communication. Cover doors and windows with draft-proofing products, replace lightweight hollow-core doors with solid ones, and replace single-pane window panels with panels with at least two panes. All of these measures can lead to significant improvements with relatively low costs, and all you have to do is continue searching for more significant options ensuring the wall is soundproof if you have been unable to reduce the noise to the desired level.

To reduce the passage of sound through a dense structure, one must either increase the mass of this structure or place an “impact absorber” between the receiving and transmitting surfaces. If there are studs in the wall, the best solution will isolate the wall surface from the grating itself using elastic pads. These lightweight metal strips attached to the studs are flexible enough to absorb and dissipate vibrations on the wall surface (much like a spring dampens mechanical vibrations).

To further enhance the sound dampening effect of the cushions, install fiberglass insulation between the studs.

If the wall is stone, a false wall grid installed 30 mm from the corresponding wall and attached to the floor and ceiling will serve the same purpose. To make a false wall, use metal studs, which are lighter, more flexible and require less space than wooden ones. You can block sound even more by filling the space between the grille and existing wall fiberglass insulating material.

These same sound control principles apply to homes. new construction with the advantage that they can be applied from the very beginning of construction. A wall in which 150x50mm studs are staggered (such a wall has two separate rows of studs sitting on 150x50mm slabs) blocks the propagation of sound between two rooms so effectively that it makes loud speech barely audible.

Through the double (100x50 mm) grille with two completely separate grilles, even a scream is barely audible. In addition, such a wall reduces low-frequency sound vibrations well.

Ceilings largely meet the same sound-attenuating properties with one exception. Noise from impacts like high heels coming from the ceiling poses particular problems. Elastic pads on ceiling beams partially eliminate such vertical sounds, but, as a rule, you have to put a thick carpet on felt, sponge rubber or cork in the places where you walk.

The basic tools and materials you'll need to complete these soundproofing projects (from building a double wall to caulking holes) are available at hardware stores. acoustic materials Some areas may need to be ordered. Since screws are better suited for installing elastic gaskets, it usually pays off if you rent an electric screwdriver or buy a set for screwing screws for a multi-speed electric drill.

Porous acoustic tiles covering the ceiling reduce noise in the room by absorbing sounds traveling through the air and transmitted through partitions to adjacent rooms. Plasterboard ceiling with elastic gaskets and the insulation between the beams does not muffle, but significantly reduces the sound transmitted to the upper room.

Sound-stopping properties of these five timber frame walls are determined by a combination of factors: the total thickness of the wall, the density and hardness of the coating material, the width of the cavity between the coating and the support, as well as the contact between them.

If a standard (100x50 mm) stud wall (picture on the left) is covered with one layer of 12.5 mm plasterboard, then ordinary speech in the next room is unintelligible. If you add a second layer of drywall, loud speech can be heard but not understood.

Best result can be obtained with one layer of drywall if added to one wall elastic pads and insert between the posts insulating layer thickness from 50 to 100 mm. Even better would be a new wall covering, isolated from the old one.(Fig. in the center). In new buildings, structural and airborne sounds can be blocked by separating and staggering opposing (100x50mm) studs on (150x50mm) studs and applying an additional layer of plasterboard to one side.

Still, a double wall is more effective- 100x50 mm. Consisting of two pairs of upper and lower harness, installed at a distance of 150 mm from one another plus a 150 mm layer of insulation between the joints, such a wall reduces sound better than a 100 mm solid brick wall.

Installation of soundproof strips.

To seal the cracks on the side and top sides doors, attach a rigid air barrier strip with flexible seal or self-adhesive strip to the jambs and header, making sure that the sealing strip is firmly pressed against closed door. To seal the gap under the bottom edge of the door, install a threshold gasket between the jambs; The gasket shown here (inset) contains a solid aluminum body with an elastic insert that compresses when the door is closed. The bottom edge of the door is slightly beveled to ensure a better fit.

Before installing soundproofing tapes, repair doors that won't close or fit poorly. For keyholes and mailboxes There are special soundproof seals.

How to soundproof a wall with studs

Remove the plasterboard to expose the underlying studs, fill the gaps between the studs with 50-100mm thick fiberglass insulation mat. On external wall the steam-resistant base of the mat should be positioned facing the room, on external wall no vapor barrier needed.

Starting as close to the ceiling as possible, attach the elastic channels to the studs, and at the very top the connecting flange, using 60 mm galvanized nails for plasterboard or 36 mm screws for dry masonry walls. Continue attaching spacers at 400mm intervals; bottom pads should be no more than 150 mm above the floor. If the connecting pieces of spacer are attached to a long wall, overlap their ends by 50 mm (Fig. inset) and place the connection on the stud.

Trim the plasterboard panels to approximately 50mm shorter than the wall height and attach them vertically to the resilient spacers using 22mm drywall screws, spaced at 230mm intervals. Use the foot lever to support each panel as you install it.

To provide additional sound insulation, attach a second vertical layer of plasterboard with 36mm self-tapping screws, positioning the joints so that they do not coincide with the joints on the first layer.

Cover the joints between the panels with tape and filler, and apply acoustic sealant around the entire perimeter of the wall (see inset).

Free-standing wall for sound attenuation

This wall with a metal stand is installed on a floor track 30 mm from the actual wall. The space between the two walls and the inherent elasticity of metal studs create a double barrier in the path of sound passing through the structural elements.

Additionally, to reduce airborne sound, the space between the posts is filled with 25mm fiberglass insulation matting. Before installing drywall, the edges of the grille are coated on all sides with acoustic sealant.

Adding an additional layer to the ceiling

Determine and mark the location of the beams; in the case of a prefabricated monolithic MARCO floor, follow the step floor beams for attaching to them. Attach the first two rows of spacers at right angles to the beams at opposite ends of the room through the fastening flanges to the beams.

Use self-tapping screws No. 38. Divide the lying space into equal intervals for other rows at 500-600 mm from one another and taking into account the location of the floor beams. Mark the position of each row by hanging a beacon line on the beams.

Attach the remaining spacers to the ceiling, making sure all flanges go in the same direction.

If you are connecting sections of spacers, overlap the ends and secure them to the beam through both flanges.

Strengthening drywall and insulation

Once all the resilient pads are in place, install the first row of plasterboard panels over them and insert 50mm fiberglass insulation strips between the plasterboard and the ceiling. If more than one sheet of plasterboard is required to cover the entire ceiling, place the joint between the two sheets through a channel (see inset).

After placing the first row of drywall, install the remaining rows, one row at a time, filling the space between the drywall and the ceiling with insulation board. Seal the edges of the ceiling with acoustic sealant and finish the joints on the drywall.

Restoration of ceiling sound insulation

Remove the ceiling, taking the same precautions as when removing damaged plaster, and install approximately 100mm thick lengths of fiberglass insulation mat, vapor barrier facing down, between the exposed joists. Attach the vapor barrier to the beams with staples.

Install elastic pads on the beams and fasten the sheets of drywall at right angles to the pads, as shown above about attaching sound insulation to the ceiling.

Using noise reduction stands

Hang two beacon lines on the ceiling at a distance of 140 mm from one another for the top trim (150x50 mm). Lower the plumb line from several points, make a mark on the floor and draw a guideline for the bottom trim.