It really depends on what sounds you want to block. It’s good in some cases and bad in others. Let’s explore those situations.
Have you ever wanted to create a soundproof room and you didn’t know what material you needed to use? I know I have been in that situation. After a little research, you probably stumbled across a specific material: concrete.
I was very confused at first as well because I didn’t know anything about it. That is why in this article I’m going to explain to you if this material is effective for those situations.
Is concrete a good sound insulator?
Unfortunately, I can’t give you a positive or negative answer. It really depends on what sounds you want to block. The truth is, concrete is a very good material for acoustic insulations but only blocks airborne noises. It is a hard material, and that is why it reduces acoustic performance in terms of impact noises.
If I confused you even more with that explanation, I will make everything clear by telling you what are both airborne and impact noises. You can figure those out only by reading their names. They are very important terms, so, if you are interested in soundproofing your house, pay attention.
Most noise that surrounds us is airborne, meaning that it is relayed through the atmosphere. Some examples of this kind of noise are real life conversations, the sound coming from television or radio, etc.
On the other hand, impact noise is a sudden burst of high-intensity sounds. It is caused by the impact of two solids hitting one another. Some examples of it are the sound of an explosion, a hammer strike, footsteps, etc.
Definition, characteristics & specs
Concrete is a composite material made from aggregate, water, and cement. It has different uses and needs time to achieve proper strength after it is mixed. It also is called normal weight concrete or normal strength concrete, as there are many types of it which we are going to discuss later.
Some of its proprieties are:
- Its density varies from 140 to 175 pcf (the unit of material density)
- Its slump varies from 1 to 4 inches
- While compressed, concrete is really strong. On the other hand, it is kind of weak while in tension
- Its air content ranges from 1 to 2%
- Unfortunately, normal concrete is not durable against severe conditions like thawing and freezing
Types of concrete
As I told you earlier, concrete comes in a lot of types with different uses. Also, they don’t share the same proprieties as normal concrete. I’m going to list those now and talk about their proprieties.
The first one I am going to cover is high-strength concrete. It is one of the most popular types, as it is typically used in the construction of high-rise structures. It is used in that industry because it has a high compression strength.
You can make high strength concrete by lowering the water-cement ratio to 0.35 or lower. An example where it is used is in the construction of highway bridges.
The next type is high-performance concrete. Compared to conventional concrete, it possesses high durability and strength. It contains one or more cementitious materials such as silica fume, fly ash, ground granulated blast furnace slag, and usually a superplasticizer.
This mix has a variety of proprieties such as high strength, workability, and durability. It has early age strength and long-term mechanical proprieties, and it is tough and permeable. Its strength ranges from 10,000 psi to 15,000 psi. It is also used in the construction industry.
Air entrained concrete
Next, we’ve got the air entrained concrete which contains billions of microscopic air cells per cubic foot. Unlike the previous types, this mix is used where the concrete is vulnerable to freezing and thawing action.
The air inside it lowers the surface tension of water, resulting in bubbles. After that, the air prevents coalescing. Those bubbles’ diameter can vary between 10 micrometers and 1000 micrometers.
However, this all comes with a drawback. Compared to the normal concrete, this type has less strength.
Another type of concrete is lightweight concrete. This mix has a density of about 105 pcf, compared to normal concrete, with a density of 150 pcf.
Sometimes you can combine this with some air entrained admixtures, which we’ve talked earlier about, in order to give it resistance to freezing and thawing and improve its strength. It is used where the extra load is not applied or to reduce the dead load.
The fifth type of concrete on our list is self-compacting concrete. It is a highly flowable type of concrete that spreads into the form without the need for mechanical vibration. It is compacted because of its own weight and is made from the same ingredients as the high-performance concrete but has increased workability.
It has extreme fluidity as measured by flow, usually between 650-750 mm. Also, another characteristic it has is that it doesn’t bleed water. It is typically used in a location where vibrations can’t reach like a deep sea.
The next interesting type is shotcrete. This type can’t be touched or held in hand, as it is just the process of placing concrete to achieve high strengths and low permeability. It is very frequently used against vertical soil or rock surfaces because it eliminates the need for teamwork.
It is popular in many industries, and it can be used for building pools, theme parks, and underground tunneling. There are a lot of products made from it, but few people notice that. Fun fact: shotcrete was actually used to form some rocks in Walt Disney World.
The following type which we are going to talk about is pervious concrete. Compared to the normal type, it has high porosity: that’s why water can pass through it. One of the main advantages is that most pervious concrete pavements don’t need much maintenance.
It provides first-flush pollution control and stormwater management. This mix allows property owners to develop a large area of available property at a low cost.
Roller Compacted Concrete
The last type of concrete I am going to talk about is roller compacted concrete. What makes it different from normal concrete is the increased durability by reducing temperature rise. It is also cheaper to transport and install.
When and why it’s used
I’ve already told you the uses of concrete in the previous section, but if you don’t want to go back to it, I’m going to make a short recap. You can use different types of concrete to build driveways, sidewalks, homes, streets, parking areas, swimming pools, etc. Although being a really good building material, it is also a good sound insulator.
My recommendation for someone who wants to build a basement will always be concrete. You have to watch out because again, it doesn’t block impact noises. So, unfortunately, you are going to hear your family’s footsteps there.
On the other hand, if you want to stop some noises from getting in a room, you can’t just destroy it and rebuild it with concrete, unless, of course, you have a lot of money to spend. If you still want to soundproof your room, you can many different materials that can be installed without breaking anything.
My number one recommendation for an alternative must be Rockwool. It is a non-combustible and lightweight product that definitely will improve the acoustics in your room. It has a lot of interesting characteristics for a pretty low price. Some of them include:
- It has high thermal efficiency. It will save you money because it will make your room warmer, acting as a second layer for your walls.
- It offers noise insulation, even for frequencies lower than 1kHz.
- It is both fire resistant and breathable material, so it will make you feel safer in your own house.
Another option would be acoustic foam. Although it isn’t as effective as Rockwool, it has some advantages over it. It can come in different colors and shapes that will surely improve your room’s design. Also, many famous studios use this material.
In a lot of cases, you will just have to unstick the thing that comes with it on the back and put in on the wall. That was it, you installed it.
Overall, concrete is a very interesting option to choose if you want to build a quiet and relaxing room or house. Before getting to work, I advise you to consult a specialist so he or she can recommend the best type.
However, you should not choose this if you don’t want to. Don’t get me wrong, I myself find it a really useful soundproofing material, but sometimes you may find better options.
The ones that I’ve listed are the most popular alternatives, and you should think of them as well when starting such an important project.
What material did you choose and why? Are you satisfied with the results in terms of noise cancelation and durability? Answer these questions and help out the whole community.