Sound insulation of an apartment

Acoustic insulation of a wall between two apartments

The Sch. Family, Cologne, Germany, reports:

We live in a multiple-family house built in 1920. The individual apartments are separated by ordinary, relatively thin walls that do not block off noises and voices, for instance people talking loudly or children shouting and crying. To remedy this situation, we decided to cover the partition walls with a sound insulation layer as part of a general refurbishment of our house.

The soniflex team recommended the construction of so-called curtain walling in front of the partition walls to block off the voices and other air-borne noises from the neighboring apartment. For such a curtain wall, a framework of 30 to 50 mm thick wooden slats is fixed to the wall, preferably on elastic spacers to ensure acoustic decoupling. Then soni PROTECT R sound insulation panels are mounted in the spaces between the slats. As a last step, plaster wallboards or particle boards are fixed on the slat framework with screws. An even better sound absorption effect is achieved when the sound protection material, here soni PROTECT R, is not fixed directly on the wall but to the wooden slats (30 mm) before mounting the wallboards.

For optimum overall effectiveness, the wallboards should be decoupled from the side walls, the ceiling and the floor by filling the gaps with acrylic putty.

Handling and cutting the soni PROTECT R sound proofing panels was totally easy and we had no trouble installing the curtain walling. For this we could rely on the detailed and sound advice provided by the very knowledgeable soniflex team. The result was just what we had hoped for: Now the sounds and noises from the neighboring apartment are virtually imperceptible on our side of the wall.

soni PROTECT R is a highly effective sound absorption material and offers higher sound insulation values than melamine foam alone. Used as sound absorber in the hollow space behind a curtain wall, soni PROTECT R achieves a considerable reduction of any resonances that might occur and thus improves the overall sound protection effect.

Sound insulation flat

The S. family, Hamburg, Germany, reports:

The noise from the apartment next door was just too much, so we had to find a noise insulation solution. We live in a maisonette that shares a wall made from limestone bricks with the maisonette next door. The building dates from 1987. Even though limestone is supposed to dampen sound, noise from various sources (radio/TV, telephone and general conversations, walking) in our neighbor’s apartment could be heard loudly through the wall. This noise problem was also perceived by our visitors.

The design of the building, especially the position of the spiral stair leading to the second floor, restricted the overall thickness of the sound-insulation curtain wall to a mere 50 mm. This led to our choice of 32-mm thick soni COMPOSITE inserted between 28-mm wood laths, on which plaster boards (2600 x 600 x 12.5 mm) were fixed with drive screws.

On both the wall and the plaster board sides, the faces of the wood slats were covered with sealing tape to minimize sound transmission.

This measure now largely eliminates any normal noises such as walking or radio/TV and also dampens the peak noises, such as a very shrill voice, to a tolerable level. 52-mm panels would probably have led to even better results, but in any case our apartment is so much quieter now than before!

Sound insulation of a ceiling

The H. family, Pforzheim, Germany, reports: Our problem was the high noise level from the apartment on the next-higher floor. To fight this noise, we needed to replace the complete wood ceiling by a new, sound-proofing construction.

In old houses it is often very difficult to define the best solution because of the special construction and building materials used. Our traditionally built ceiling, for instance, was filled with straw and cinder.

We sent soniflex an email describing the problem. They answered promptly with an exact description of what the new ceiling construction should look like and a list of the materials needed.
We ordered soni PROTECT R acoustic panels and cartridges of soniflex special adhesive which were delivered via DHL.

For the new ceiling construction we used wood laths (4.8 x 5.8 cm) fixed to the walls at both ends and to the ceiling beams at several intermediate points, wherever possible.
The question was how to ensure acoustic decoupling from the existing ceiling. And we had an idea: We simply cut some soni PROTECT R panels to fit the laths’ width and inserted it between the new laths and the old ceiling. This was pretty easy to do and the best solution for preventing noise transmission.

Then the soni PROTECT R acoustic panels were glued between the laths on the old wood ceiling, using the special soniflex adhesive. The adhesive could be applied either in individual dots or in a zigzag pattern, as best fit the situation.

Then plaster boards were fixed to the laths, the gaps filled with putty and the surface smoothed.

With the 5.8 cm thickness of the laths and the additional soniflex material between laths and old ceiling, there was a hollow space of 0.5 to 0.8 cm left between the soniflex material and the plaster board. According to soniflex, the air in this space acts as an additional insulation layer.

We also followed the instructions of soniflex to leave a gap between the plaster boards and the wall and fill it with an acrylic sealing material for acoustic decoupling of the boards and the walls.

With the support of soniflex and of course their soni PROTECT R material, it was possible even for laypeople like us to achieve a very good sound protection result

Insulation of the bedroom against neighbourhood noise

The W. family, Berlin, Germany, reports:

After having moved in our end-terrace house we realised that habitation noise (such as moving noises and loud music) of our neighbours were clearly perceptible. These noises were particularly disturbing in our bedroom. We therefore decided to insulate the adjacent wall to our neighbours. After having installed the self-adhesive sheets soni COMPOSITE on the concrete wall, the air-borne noises (voices, loud music) were no longer perceptible. The footfall sound noises were considerably reduced.
We are very satisfied with this result and the anthracite sheets are very decorative, as shown in our photos.

Sound insulation of a bedroom wall against noise from the neighboring apartment

Sound insulation of a bedroom wall
Mr. U. from Munich (Germany) reports:

In my bedroom, I was often bothered by the noise from my neighbors’ living room, for example the sound of voices, the television, music or laughter. As I live in a rental apartment and my bedroom is quite small, the construction of curtain wall for sound proofing the partition wall as recommended by soniflex seemed too expensive a measure. The curtain walling would also have taken up too much of the limited space. This is why I decided in favor of the simpler alternative of fixing soni COMPOSITE 52-mm sound protection panels directly to the wall surface. As a large wardrobe was to be put right in front of the wall in question, covering it almost in its entirety, fixing the sound protection panels with adhesive was perfectly sufficient and I didn’t even need to fix the panels mechanically or cover them with plaster wallboards, as recommended by soniflex for such applications in general. The wardrobe not only ensures that the sound protection panels will not come loose, but also provides additional sound insulation.

In combination with the wardrobe, the soni COMPOSITE sound protection panels fixed directly on the wall proved to be the right solution for the protection of my bedroom against the noises from the neighboring apartment, which are virtually imperceptible now. I am absolutely satisfied with the result. And, what is more, it was really easy to install the sound protection panels.