Noise is around us on a daily basis. However, as the time goes, we get used to a certain noise and don't hear it anymore. At this stage, a total silence makes us feel even uncomfortable. That‘s why we turn on television, listen to music, talk to our relatives. Though, if your neighbours listen to music or watch television so loud that even you can hear it, that comes as a problem. A problem can also become present when your neighbours start complaining that the music sound from your home comes as too loud. In order to avoid the problems mentioned above, residential spaces should contain special acoustic conditions that would satisfy both sides - us and our neighbours.
The main reasons of poor sound isolation in large-scale houses, especially the ones of the older construction are the joints of stiff reinforced constructions, holes in walls and spans which contain fixed electricity sockets and ventilation channels. The sound goes through concrete - good vibration conductor which strenghtens the sound even more. So what aspects should be considered whilst creating appropriate acoustic conditions?
Floor isolation
If you want to isolate a bang sound, its best to design "floating" flooring - elastic and effective sound suppressive panels between the present span panel and top floor lining layer. They can be made of stone or glass cotton as these materials are almost the best noise conductors. Whilst laying isolation panels on interheight span between the top lining layer and the wall construction, it is essential to assemble an isolation in-between span. It is also important to ensure that the top lining layer would not adjoin other building constructions. It should be remembered not to leave air gaps between flooring panel and walls, and even better to fill it will elastic span so that the bang sound would not be transfered to surrounding walls. This tool will be effective only if the space will have "floating" flooring designed.
Partition isolation
Whilst increasing the thickness of the partition due to lower resonant frequencies, sound isolation features of all construction are improved. However, we won‘t get expected results if we only increase the thickness of the partition without having it filled. We will get good results if we at least partly fill the partition with an isolating material.
Multi-layered partition should be designed in a way that the energy of the sound wave inside the construction would be absorbed and spread. You can achieve this if you fix a multi-layered construction of plaster carton sheets on both parts of the partitions by filling the hole with a stone cotton. A three-layered bricked partition can be made of bricks or small blocks as well as stone cotton in between them.
Whilst designing partitions in newly-built areas, first of all it is recommended to design the partitions, later a lining layer or "floating" flooring. Partition joining with other building parts have a big influence when joints become the bridges of the sound. In such case it is recommended to use elastic in-betweens. Due to poorly designed or fixed partitions, the sound isolation features can disimprove up to 10 dB (first of all due to a side sound spread).
In the process of construction, you should not leave building waste or rubbish in partitions (plaster carton strips, bricks). Due to these, the stiffness of the aggregate increases together with resonant frequencies resulting in poorer sound isolation features of the partition.
Ceiling isolation
To isolate your ceiling from a bang sound which e.g. is caused by your neighbours is not an easy task. This should be done by your neighbours whose steps or piano playing get through to you.
The ceiling should be isolated when your neighbours complain of the noise going from your space. What is more, if you prefer to have your space less noisy, i.e. with less echo, ceiling isolation could be a great solution. Special hanging acoustic ceiling is the most effective at sound absorbing, however, it should be hanged on elastic holders - ordinary metal holders will not do in this case.
Door sound isolation
Whilst choosing the apartment entrance doors, you should consider whether you want to secure the inside space from outside noise. The door sound isolation features inside the apartment can be chosen according to your requirements. In C class sound buildings it is recommended to use doors whose door rate is no smaller than 33 dB. In B class sound buildings, the door ration should be no smaller than 38 dB.
Window glazing
In order to reduce the noise coming from outside, a double window glazing could be used. Double or triple glass packs increase isolation from outside noise. To achieve a great noise isolation, the glazing gap is designed with different layer glazes; or they can be layed in different corners. If you want to avoid the resonant vibrations, quite often present in two membranes of a similar mass, both options can be used at once. Even a better sound isolation can be achieved if a transparent sound wave absorbing screen (sheet) is placed between the glazes.
Fasade and roof isolation
Fasade isolation panels not only warm-up the building but also increase the air sound isolation ratio of the outside building wall even up to 20 dB. However, it should be remembered to fill window and other gaps in the layers of the top walls.
Outside noise can be reduced by isolating the roofs with stone cotton tools. One layer of the product is placed between the balks, another athwart to the first one, accross the balks. This method helps to reduce the outside noise effectively.
Other methods
- Fixing of gaps. The fixing of all gaps helps to isolate the sound. High frequency noise gets through these gaps.
- It is recommende to place equipment sound sources on a soft covering: special sorky wood or rubber mats. You should avoid fixing them to the walls. It is also better to choose a curtain or corky wood flooring.
- The noise coming through pipes, channels or communication devices from one area to the other can be reduced if you install the sound isolating spans in crossings of such communications and walls.
In order to achieve good results, its not enough to use suitable materials for sound isolation. If you do not stick to technologic requirements or uncarefully design the construction, the ability to isolate the sound can be decreased in more than a few decibels. The job quality of a builder is very much important. It is essential to fix all the holes, scrathes as even the smallest gap becomes a soud bridge.
