Best Blown-In Insulation Types For Soundproofing

When you are living in a big city or noisy environment, soundproofing your home is a necessity. There are tons of acoustic insulation that can shut the outside noises out and make your house feel like a home. However, the abundance of options makes it hard to choose the right product sometimes. So, are you wondering which blown-in insulation type is best for soundproofing? Lucky for you, we have got the answer to your question.

The best blown-in insulation types for soundproofing are loose-fill cellulose and fiberglass insulations. Both of these insulations have a high R-value and high STC value. Not only that, but these products also offer thermal insulation, which means you would not have to get separate insulation installed for thermal insulation.

Of course, there's more information you might want to know. For example, what's the best R-value for soundproofing? Additionally, how effective is insulation at being able to dampen sound? After all, we wouldn't want to spend more than we should if it doesn't make a substantial change. So, if you'd like to know this and more, keep reading ahead. 

A worker spraying blow-in fiberglass insulation in the attic

Does Blown-In Insulation Provide Soundproofing?

Yes, blown-in insulation also provides soundproofing. It is one of the main reasons why fiberglass and loose-fill cellulose insulations are so popular. Because not only does this blown-in insulation trap the heat inside and reduce energy bills, but, also makes the house soundproof.

Cellulose insulation applied in the wooden framing of a house

What Is the Difference Between Soundproofing Insulation and Regular Insulation?

When buying insulation for your home, it is crucial to research the different types available. You would not want to get soundproofing insulation for thermal insulation and vice versa. But why is that such a huge problem? Well, because both of these insulations are widely different.

A white hose used in spraying fiberglass insulation

For starters, as the names suggest, soundproofing insulation is used for sound dampening purposes. It prevents sound from coming in or out of the house.

On the other hand, other insulation offers thermal insulation. This type of insulation prevents the heat from escaping out of the house or entering the house. Other than that, there are a few differences between soundproofing insulation and regular insulation, so let’s discuss more of those.


First, soundproofing insulation generally composes of a material such as mineral wool or foam with MLV or drywall. On the other hand, the most common and commonly used regular (thermal) insulation includes cellulose or fiberglass.

Cost & Availability

Soundproofing insulation is also hard to get. Due to a low rate of production, soundproofing insulation is usually higher in price than thermal insulation.


Another difference between soundproofing and thermal insulation is the density of both of these products. Thermal insulation has an average density of between 0.75 and 3 pounds per cubic foot. And soundproofing insulation, on the other hand, has a density of 3 pounds per cubic foot.

The Best for Soundproofing

So, now that you know the difference between both of these insulations, which one is better for soundproofing? Even though both are easy to use, acoustic insulation is best for soundproofing. It has around a 50 STC (Sound Transmission Class) rating.

Meanwhile, thermal insulation sits at 36 STC. The higher the STC, the better the soundproofing is. Acoustic insulation works best for soundproofing.

What R-Value Insulation Is Best for Soundproofing?

R-value is the rating of how well insulation can resist heat transfer. But R-value also shows how good insulation can barricade air transfer. And as sound transfers through the air, low air transfer sometimes can indicate less sound or acoustic transfer. 

R-value is generally now the first thing that people check when buying soundproofing insulation. In general, the higher the R-value, the better the insulation can absorb sound. 

Some recommend using R-13 insulation for walls and R-19 insulation for the ceiling when soundproofing a room.

What Is the Best Sound Insulation Between Floors?

When soundproofing a house, installing acoustic insulation in the walls and ceiling is not enough. To reduce as much airborne noise, you need to insulate the floors as well. If you are looking for the best sound insulation between floors, here are some great options.

Experts suggest using DFM acoustic insulation between floors for soundproofing. This insulation is one of the best for reducing the transfer of airborne noise. Moreover, for best results, use a 100mm floor insulation density between 3-3/4 to 5 lbs per cubic foot.

How Effective Is Soundproof Insulation?

Soundproof insulation is one of the best ways to prevent sound from transferring. The acoustic insulation prevents the outside sound from coming in and reduces the sound transfer between different levels of the house.

The effectiveness of soundproofing also depends on the type of insulation you are using. For instance, foam insulation can deafen around 80% of noise.

However, sometimes even after getting soundproofing insulation installed, you can still hear outside noises. It can indicate that you might need to install more insulation for better soundproofing.

How Long Does Blown-In Insulation Last?

A worker rolling fiberglass insulation in the attic

Blow-in insulation such as loose-fill cellulose has a life expectancy of 20-30 years. This insulation can last for around three decades. However, several factors can affect the life expectancy of this insulation.

The Disadvantages

For starters, moisture is one of the elements that can lessen the expectancy of blow-in insulation. For example, cellulose insulation is made of discarded paper and cardboard, which are susceptible to moisture damage.

In case of a minor leak, the entire insulation can get damaged. Not only that, if this damage does not get detected in the earlier stages, moist cellulose can also lead to mold infestation.


Another factor that affects the life expectancy of blow-in insulation is settling. Settling is a common term used to refer to the settling process of blow-in insulations. As blow-in cellulose material is fluffy, it can settle down over time.

The settling rate for blown-in insulation is as high as 20-30% within the first few weeks after the installation. However, settling down can be avoided by adding more insulation during the installation.

Air Leaks

The last factor is existing air leaks, which can lessen the life expectancy and effectiveness of the insulation. It is why the first process of installing blow-in insulation is sealing the area to prevent air leaks. However, if you have already installed the insulation, detecting air leaks is quite hard.

Fiberglass vs. Cellulose Insulation: Which Is Better for Soundproofing?

A worker spraying blow-in fiberglass insulation

Both fiberglass and cellulose insulations are some of the best blow-in insulations in the market, but which one is the right choice for you? Let us find out. The following are the main differences between fiberglass and cellulose insulation.

The first difference is that cellulose insulation is made from discarded paper and cardboard. Hence it is organic insulation. On the other hand, fiberglass is made of tiny synthetic glass fibers. Due to this, it can cause itchiness and is uncomfortable to work with. Furthermore, fiberglass is notorious for causing breathing problems.

In terms of R-value, cellulose insulation pulls ahead. It has a 3.4 R-value, while fiberglass only has a 2.2 R-value. In other words, cellulose insulation is better at preventing the air from escaping. Hence, it is better at soundproofing the airborne noise.

How Do You Soundproof the Exterior Walls?

Soundproofing exterior walls are as important, if not more, than soundproofing the interior walls. But how do you soundproof exterior walls? Instead of using the same blown-in acoustic insulation, use the following methods to soundproof the exterior walls.

  • The easiest and common way to soundproof an exterior wall is by using a Green Glue compound to glue  5/8-inch drywall.
  • Another way to soundproof exterior walls is by adding LB or 2 LB mass-loaded vinyl (MLV). After that, add another 5/8-inch drywall on top of it.

What Are the Best Soundproofing Materials?

Blow-in insulation offers good soundproofing, but what if you cannot get them installed. Are there other options? Yes, there is always another option. And when it comes to soundproofing, there are plenty of options. The following are some of the best soundproofing materials in the market.

Foam Insulation

Foam insulation is one of the easiest to work with. It comes in a spray can, which you can install yourself. As foam insulation is flexible, it is considered best for using between the walls and floors.

Mass Loaded Vinyl Sound Barrier

This material might not be as flexible as the foam insulation, but mass-loaded vinyl still offers good soundproofing. You can use this between walls, ceiling, floor, and even between hollow doors.

Acoustic Caulk

Sometimes the tiny cracks in the walls and doors let the noise inside. For situations like this, you can use acoustic caulk.

Final Takeaway

Whether it's noisy neighbors or an attempt to prevent sound from leaving your room for band practice, it might get confusing finding the right soundproofing insulation. But, doing a little bit of research can help you narrow down your decisions! We hope you found the information above helpful! 

Before you go, do you have other insulation concerns? Are you curious to find out the weight of spray foam insulation? As mentioned above, it can also help with soundproofing! If you want to find out more, check out our post here.

Are you considering all your options for soundproofing and insulation? You might be surprised to find that curtains can help! If you'd like to learn more, check out our post here. Until next time!

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