The Best Insulation Types for Soundproofing

Insulation’s primary function is to keep your home comfortable by preventing unwanted heat or air from entering and escaping. While this is most important, insulation does have additional benefits. Each form of insulation has its own unique benefits. One benefit of all forms of insulation share is that they have some ability to reduce noise, some doing better than others.

Insulation has two values that are important for soundproofing. The first is the Noise Reduction Coefficient (NRC) value, which means the insulation’s ability to absorb sound. The NRC value is on a scale from 0.0 to 1.0, with the higher the value being, the more sound it can absorb. The second is the Sound Transmission Class (STC), which measures how much sound the insulation blocks. The higher the value, the more noise the insulation can block. Read on to learn about the forms of insulation that can help decrease sound from traveling through a house.

Cotton Insulation

Cotton insulation, also known as denim insulation, is one of the best forms of soundproof insulation with its high NRC value. Cotton insulation is ideal for reducing noise, but it does have a lower R-value, meaning it isn’t ideal for colder climates. While it is considered eco-friendly insulation since it is made out of recycled denim, it is more expensive than other forms of insulation with a higher R-value.

What is the NRC of cotton insulation?

The NRC of cotton insulation is 1.15, the highest on our list. 

What is the STC of cotton insulation?

Cotton insulation STC rating is 51.

Spray Foam Insulation

Closed cell spray foam insulation can help decrease sound that travels from room to room in your home. Spray foam insulation can get into small cracks and places. Getting into a home’s nooks and crannies helps prevent unwanted air from entering and exiting these areas, but it also prevents noise from traveling throughout a home. Spray foam insulation is frequently used in walls before drywall is placed as well as opened areas such as basement rim joists.

What is the NRC of spray foam insulation?

Spray foam insulation has an NRC rating of .70.

What is the STC of spray foam insulation?

The STC rating of spray foam insulation is 39.

Fiberglass Insulation

Fiberglass insulation is a popular choice for soundproofing. The glass fibers are densely packed together forming a porous material that can help absorb sound waves, thus blocking out noise. Fiberglass insulation is commonly used in ceilings to help decrease the sound of someone walking above you. It is also frequently used to insulate the walls of homes.  

What is the NRC of fiberglass insulation?

Fiberglass insulation has an NRC rating of .9-.95.

What is the STC of fiberglass insulation?

Fiberglass insulation has a 39 STC rating.

Mineral Wool Insulation

Mineral wool insulation is made of rock fibers, similar to fiberglass insulation. It is denser than fiberglass making it more effective at reducing noise. When used for soundproofing, mineral wool insulation can help to reduce noise transmission through walls, floors, and ceilings by absorbing sound waves and reducing resonance. Mineral wool is an eco-friendly form of insulation, but it can be harder to find and not as easy to install.

What is the NRC of mineral wool insulation?

Mineral wool insulation is one of the best NRC values at .95 and up.

What is the STC of mineral wool insulation?

The STC rating of mineral wool insulation is 45.

Cellulose Insulation

Cellulose insulation is not as dense as other forms of insulation but does still provide some noise-reduction properties. It is one of the most cost-effective forms of insulation to help with soundproofing, especially when you consider its thermal insulation properties too. Cellulose insulation is excellent at blocking out road noise, making it a great choice to insulate exterior walls with. It can also help decrease sound from traveling from room to room when used on interior walls.  

What is the NRC of cellulose insulation?

The NRC of cellulose insulation is .80 and up.

What is the STC of cellulose insulation?

Cellulose insulation has a 39 STC rating.

Interested in improving your home’s insulation?

Certain forms of insulation can help provide noise reduction, but no form of insulation can eliminate noise entirely. If you are looking for a way to decrease sound from traveling throughout your home while also improving your home’s comfort, contact Ecotelligent Homes.