Soundproofing insulation is a key aspect in the process of soundproofing a room. It is a special type of insulation product, designed to be an acoustic barrier that absorbs sound and can greatly reduce noise transmission from one room to another.
Whether you are remodeling or building from scratch, having a good plan for soundproofing your walls, ceilings, floors, and even doors will set you up for a successful project. The result of installing the best soundproofing insulation will be a peaceful and private home or business environment for all to enjoy.
The rest of this guide will explain the many different types of insulation you can choose, where to buy it, where to use it, and how to install it. Once you understand the basics of this awesome and affordable soundproofing material, you’ll be ready to reap the benefits.
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Benefits of Soundproofing Insulation
First, it is helpful to drive home the point that soundproof insulation is an acoustic barrier, not an acoustic treatment. That is, if you are wanting to make the sound in your room sound better, you should be looking into treatments like acoustic paneling, acoustic curtains, and acoustic foam panels. Soundproofing batts help block unwanted sound from entering or exiting in the first place by adding density to the construction of your walls and floors.
- Reduce Outside Noise – Anybody who has lived or worked near a busy highway knows what a constant distraction the noise can be. Soundproofing the exterior walls of a building with mineral wool can help reduce the amount of road and city noise making its way inside.
- Reduce Noise Leakage Indoors – Just like outside noise, soundproofing batts installed inside your interior walls can improve the sound environment indoors. The barrier prevents sound from exiting, as well as blocks unwanted sound from entering. You can imagine the benefits this can provide in homes, home theaters, studios, and office buildings.
- Thermal Insulation – You might be surprised by this, but mineral wool, one of the most common soundproofing insulations, also has good thermal insulating properties. You won’t have to sacrifice the ability to keep your building warm or cool when using this type of product.
- Increases Home Value – Soundproofing your home with insulation is viewed as an upgrade in the real estate world. With it, your home’s value could be higher than others in your neighborhood, especially in densely populated areas, and those located near high traffic roads and highways.
Best Soundproofing Insulation: Acoustic Performance
There are three main types of materials used in acoustic insulation products: mineral wool, fiberglass, and cotton-based materials. Here is a brief explanation of the materials, followed by a table comparing the acoustic performance.
- Mineral Wool Soundproofing – Also known as stone wool, or rock wool, this material has been around for many decades, but advances have been made in performance to make it ideal for soundproofing applications while not sacrificing the thermal insulating capabilities. Mineral wool is a natural material made from molten basalt and has excellent natural resistance to fire and moisture.
- Fiberglass Soundproofing – Fiberglass is an affordable alternative to mineral wool that has nearly the same acoustic properties, but is not quite as good thermally, and is not a natural material like mineral wool. Fiberglass is more challenging to work with and requires precautions to handle the fine glass fibers safely.
- Cotton Soundproofing – Cotton based insulation is a cheaper material than fiberglass and is natural, but as a result, it is less versatile than fiberglass and mineral wool. Acoustically, it’s still a good product, as good or better than either, just not quite as high performance and no fire resistance.
| Product | NRC | 125Hz | 500Hz | 1000Hz | 4000Hz | Density |
|---|---|---|---|---|---|---|
| Mineral Wool – High Performance | ||||||
| Roxul Rockboard 60 (2in) | 0.95 | 0.32 | 1.06 | 1.02 | 1.04 | 6.0 lb/ft^3 |
| Roxul Rockboard 80 (2in) | 1.00 | 0.43 | 0.90 | 0.97 | 1.00 | 8.0 lb/ft^3 |
| Roxul Acoustic Fire Batts (AFB) | 0.95 | 0.28 | 1.09 | 1.09 | 1.07 | 2.5 lb/ft^3 |
| Safe'N'Sound by Roxul | 1.05 | 0.52 | 1.18 | 1.07 | 1.05 | 2.5 lb/ft^3 |
| Fiberglass – Multi Purpose | ||||||
| ATS Acoustics Rigid Fiberglass (2in) | 1.00 | 0.29 | 1.11 | 1.13 | 1.03 | 3.0 lb/ft^3 |
| Owens Corning 703 (1in) | 0.70 | 0.11 | 0.68 | 0.90 | 0.96 | 3.0 lb/ft^3 |
| Owens Corning 703 (2in) | 1.00 | 0.17 | 1.14 | 1.07 | 0.98 | 3.0 lb/ft^3 |
| Owens Corning 705 (1in) | 0.65 | 0.02 | 0.63 | 0.85 | 0.95 | 6.0 lb/ft^3 |
| Owens Corning 705 (2in) | 0.95 | 0.16 | 1.02 | 1.01 | 0.99 | 6.0 lb/ft^3 |
| Cotton Batts | ||||||
| ATS Acoustical Batts | 1.05 | 0.27 | 1.17 | 1.15 | 1.06 | 2.5 lb/ft^3 |
1. Roxul Rockboard 40/60/80
Roxul Rockboard is a rigid mineral wool panel product ideal for use as noise and thermal barriers. Rockboard is perfect for blocking noise in mechanical rooms, or any interior room where sound absorption and thermal insulation are both a priority.
While Rockboard has slightly lower sound absorbing performance, especially at lower frequencies, they have improved thermal insulating capabilities. With R-values over 4 per inch, these products could be used on the inside to soundproof exterior walls on top of standard thermal insulation.
Rockboard comes in three densities, 40 is 4 lb/ft3, 60 is 6 lb/ft3, and 80 is 8 lb/ft3. All boards are 24” wide and 48” tall and come in thicknesses from 1” up to 4”. The thicker the panel, the better the acoustic performance at the lower frequency levels. If your application has deeper, bass style noise, you’d better be using a 4-inch thick Rockboard.
2. Roxul AFB (Acoustical Fire Batts)
Rockwool AFB is a similar Roxul product to Safe N Sound, sized specifically for steel stud walls or floors on the inside of commercial buildings. It’s also fire-resistant, water repellent, and won’t rot, sag, or attract mold.
It’s also much easier to find than Safe N Sound, so don’t let the “steel stud” sizing prevent you from considering it for your project. Steel stud batts are wider than wood stud batts, so you could simply slice a strip of material off the sides and stuff it into your cavity. It can also be used for other projects like voice booths, studios, and more.
AFB has an excellent sound absorption coefficient (SAC) of 0.95 and great performance at mid to high frequencies. The high density also aids in the reduction of low-frequency vibrations that can be so distracting.
3. Auralex Mineral Fiber Insulation
This Mineral Fiber insulation from Auralex is a high-performance mineral wool product and a great alternative to Safe N Sound. The best part is it’s easily available online from either Amazon or Auralex. The Auralex panels have a crazy high 8 lb/ft3 density, and the same qualities of thermal insulation, and fire and moisture resistance as Roxul.
- High performing mineral wool insulation.
- Two thicknesses (2” / 4”) available, providing options for any project.
- Excellent soundproofing over a wide range of frequencies.
- Material: Mineral Wool
- Density: 8 lb/ft3
- Thickness: 2 in / 4 in
- Sizes: 24 in x 48 in
The mineral fiber insulation comes in 24” x 48” panels, in both 2- and 4-inch thicknesses. 2-inch panels come 6 per box, and 4-inch come in 3 per box. For the best thermal properties, select the 4-inch version and get a combined R-value (insulating rating) of 4.2 per inch.
The 2” has an NRC of 1.0, and the 4” achieves an NRC of 1.05, putting it on par with Roxul Rockboard panels of the same thickness. The 2” thick batts provide soundproofing over a great range of frequencies, but the 4” will have the best low frequency performance.
4. Roxul Safe N Sound
Safe N Sound insulation is a high performing mineral wool product that is perfect for soundproofing interior walls and ceilings. This product has superior fire resistance and excellent acoustic qualities, making it the best choice for soundproofing a variety of residential rooms.
- Best insulation for interior soundproofing projects.
- Excellent noise reduction across many frequencies.
- Fire, Mold, and Mildew resistant.
- Material: Mineral Wool
- Density: 5 lb/ft3
- Thickness: 3 in
- Sizes: 16 x 48, 24 x 48 Wood or Steel Stud
Safe N Sound comes in two sizes, one for wood stud walls, and one for steel studs. Both are 3 inches thick, but steel stud batts are 1” longer and wider than a wood stud. Be sure to get the right one or the batts won’t stuff into the stud cavities as they should.
It has an NRC of 1.05, tops in the category, and best in class NRC at low frequencies and among the best at higher frequency ranges. The one issue with this product is finding a place to buy it. Many times, you’ll have to special order it if your local home improvement store doesn’t carry it.
5. Owens Corning 703 Fiberglass
Owens Corning is a familiar name in the industry, and the 703 fiberglass acoustic insulation has long been a go-to material for soundproofing projects. Mineral wool products have since taken away some of that popularity, but 703 fiberglass panels remain an effective soundproof insulation option.
- High performing fiberglass soundproofing insulation.
- Well known and trusted brand name.
- Easy to find a supply, although comparatively expensive.
- Material: Rigid fiberglass
- Density: 3 lb/ft3
- Thickness: 1 in / 2 in / 4 in
- Size: 24 in x 48 in
Owens Corning 703 comes in 24” wide by 48” tall boards, in 1, 2, and 4 inch thick panels. Just like the best mineral wool insulation, you’ll want thicker fiberglass boards for better low frequency acoustic performance. For example, at 125 Hz the 1” boards have a SAC of 0.11 while the 4” boards come in at 0.84.
703 is widely available, but it’s pricey. 4 inch 703 can cost more than 2 layers of Rockboard or AFB, which may or may not be a big deal depending on the size of your project. ATS Acoustics Rigid Fiberglass is an excellent alternative product that looks and performs nearly identical to 703.
6. ATS Acoustical Cotton Batts
If you’re interested in more eco-friendly insulation that still has excellent acoustic properties, then look no further than ATS Acoustical Cotton Batts. ATS Manufactures the batts from a minimum of 85% post-industrial cotton fibers, and the batts themselves are 100% recyclable.
- Sound absorption on par or better than fiberglass.
- No nasty chemicals, VOC’s, or itchy fibers.
- Eco-friendly, recyclable, and resistant to microbial growth.
- Material: Cotton Fiber Batts
- Density: 5 lb/ft3
- Thickness: 2 in
- Size: 24 in x 48 in
If you have a LEED requirement this may be your best and the only option, however, it is not recommended for any application that requires fire resistance. While it’s not fire rated, it does have a great microbe resistance.
The acoustic performance of ATS Cotton Batts is comparable to Owens Corning 703 and comes at a cheaper price. The flexible nature of cotton batts requires a rigid frame or backing, and it boasts SAC ratings over 1.0 for frequencies of 500 Hz and higher.
Installation Tips
Mineral wool and fiberglass soundproofing insulation can be purchased in packages of multiple panels or rolls of batts, depending on the type. They are manufactured with good tolerances and fit snugly in between wall studs and ceiling joists. They fit easily into the cavities with a friction press fit, ensuring there is no air gap for sound to leak into adjoining rooms. A simple bread knife with a serrated edge is enough to cut the batts to size.
The insulation panels are typically 2”-3” thick and are rigid enough to be easily cut to shape around electrical outlets and studs. You can use a drywall saw to precisely cut out the notches to make each panel fit into place. Wall and ceilings can be finished off with standard or soundproof grade drywall, no vapor barriers are required.
Soundproofing insulation panels can be purchased for wood or steel stud walls and ceilings. Make sure you pick the right version, or they won’t fit well in your wall cavity. Here are typical sizes of batts:
- Wood Stud Panels: 15.25” x 47” x 2” or 3” Thick
- Steel Stud Panels: 16.25” x 48” x 2” or 3” Thick
Of course, soundproof insulation is only a part of what possible. You can choose to go all out and build decoupled walls using a hat channel, acoustic sealants, and two layers of drywall. Either way, you’re making a great investment in the comfort and utility of your home!
*Last updated 2024-10-10 at 17:01 / Product Links & Images from Amazon Product Advertising API
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I am investigating the options to finish the interior of a standard 1 car detached garage for the purposes of a music room/studio. I would like to soundproof the walls as best as is possible. Can you make any recommendations and prices to do so. Thank you in advance, and I look forward to hearing back.
Since it’s detached, I think Roxul AFB would be a good option for your garage. You’ll get good acoustic NRC, as well as decent thermal insulation.
You should also double up on your drywall, and use some green glue between the layers. As for cost, well, that depends on how big your garage is 🙂 Measure the walls, then use the info on this site to calculate total cost.
I live in a condo that has someone living above me. The noise of just walking back and forth in bear feet is so annoying, you can imagine what it is like with shoes/high heals on. There is also a dog and cat that play. The owner recently put in hardwood floors with a sound barrier underlayment from Lowe’s. I can tell you it does not work. I get woken up daily when the dog jumps off the bed. A huge thud or crash sound.
I’m remodeling my bath and have a section of the ceiling torn out. What product could I use that would lessen or eliminate all of the noise coming from my upstairs neighbor? Cost is a factor as is installation as I’m not willing to take down all of my ceilings. Thanks for the help.
Hi Nancy. In your bathroom, since you have the ceiling torn out, I would install Roxul AFB or Safe N Sound between the ceiling joists. On the rest of your existing ceilings, due to your desire to not take it down, I would consider scraping off any old popcorn finish, apply Green Glue across the bare drywall, and then install a second layer of drywall on top of that. The Green Glue should help decouple the ceiling, and the drywall adds sound dampening mass.
maybe install extension-type electrical boxes, adjust potlight canisters 1″ down to new ceiling height, acoustic caulk around wires / openings, fill box cavities with rockwool, then either a layer of drywall on resilient channels, or suspend acoustic tiles in tee-bar.
I just bought a house on a busy road. The master bedroom is closest to the street. We just installed triple-pane windows hoping that would significantly reduce the road noise (and because the old windows were very old and inefficient). It worked okay, but we want to soundproof even more by ripping out the drywall and installing insulation and/or another type of sound reducer.
What would you suggest is the best course of action and best product(s) to use?
Thanks!
Dave,
On exterior facing walls, you would be sacrificing thermal insulation by using these sound insulation products, but they would be fine for the other interior walls. You might want to look at just adding another layer of drywall with Green Glue sealant in between the layers. The added mass of the drywall and the decoupling by the Green Glue should help.
I have a portable washing machine (Haier HP23E), my neighbor saying its too loud, they can hear it through the wall/floor and would like to sound insulate/proof it like putting some material around it that would hold up the traveling noise of the machine. I can’t do anything with the walls as the apartment is rented and would like to keep my washer…. I live ground floor and have upstairs neighbor, washer is in small bathroom, the other side of the bathroom is sitting room/hall way.
thank you
Susie V,
Perhaps you can create a box around the machine, and line it with a material like Mass Loaded Vinyl. There are several products that could suit your situation well in this post – https://www.soundproofingtips.com/mass-loaded-vinyl/
You may also want to try mounting it on rubber feet so that vibrations are not so easily transmitted through the floor and wall.
Hi, I just purchased a house right next to the railroad cross where they blow their whistle, it passes as much as 4x a night, I have the house demo’d down to studs and I was wondering how I should insulate to try to block as much sound as possible, I was also wondering if it is worth buying 3 paned windows by Pella?
Thank you very much!
Jeanne
If I understand correctly, you’re talking about exterior walls, so you really don’t want to sacrifice thermal insulation for sound insulation. I think you could use a high quality spray foam insulation to fill in all the air gaps between studs, then use 2 layers of drywall with Green Glue applied in between. As for the windows, if you do a good job on the walls, and don’t do the windows, it becomes the weak link. If you can afford to do it now, it may be best in the long run. Good luck!
I have a situation where I need to insulate a floor, the framing is existing but we are pulling off the ceiling drywall. The floor above has hardwood.
My client wants to maximize the soundproofing between the levels.
I am suggesting cotton or fiberglass insulation with resilient channels and quiet rock drywall. I am too familiar with the mineral wool insulation; do you recommend that over fiberglass or cotton for maximum soundproofing?
Thank you.
My opinion is that mineral wool would be better for the ceilings. A product like Roxul AFB provides a good Noise Reduction Coefficient and has the added benefit of fire retardant. Check out how the pros do it in this video.
We want to prevent road noise coming through the gap at the top of the garage door through the garage ceiling into the two bedrooms over the garage. We are not worried about impact noise. Roxul Safe N Sound appears to be the solution for airborne noise. If we attach the drywall to the joists without resilient channels after installing Roxul, will this conduct airborne noise into the bedrooms?
What temperature insulation can be used with Roxul?
What airborne noise insulation and temperature insulation can be used in the exterior bedroom walls over the garage?
I would try to address the gap in the garage door first, perhaps with some heavy duty weather stripping. Then, like you suggest, insulated between the joists. Safe N’ Sound is not as great of a thermal insulation as say, spray foam insulation, but it should help with sound transmission. Then dry wall over the joists. If one layer is not having the desired effect, then apply Green Glue in between a second layer of drywall, which is much easier than resilient channel.
How effective is expanding foam at acting as a sound barrier in a cavity compared with mineral wool?
Expanding foam is an interesting alternative. Compared to mineral wool batts, the spray foam does a good job sealing all air gaps where sound can leak, but doesn’t have the near the density of mineral wool for sound insulation. The kind of foam that results in a rigid foam (closed cell) doesn’t do much good for sound mitigation, but the kind that dries in a spongy state (open cell) is better. I have talked with builders who recommend spraying a 2-3″ layer of the soft foam to seal, and then finishing the wall cavity with Roxul AFB or fiberglass batts. Hope that helps.
Hi, I own on a side by side duplex on a somewhat busy road. there was fiberglass batts in the crawlspace when I moved in but have since been removed because they were falling apart. I hear a lot of the stepping around from my next door neighbors. I also hear some of the pipes in the crawlspace when they turn on the water. occasionally I hear them speak as well. I have added lots of attic insulation (blown in fiberglass). I have added a layer on greenglue and 5/8 drywall to the adjoining bedroom walls (hasn’t helped much and it was about 3 weeks ago). I think a lot of the noise is transferring through the crawl space. I was thinking of installing R23 roxul batts (This would meet the thermal requirement too, the safe n sound, seems to be too light for thermal needs). but I keep reading there isn’t as much of a difference in noise reduction between fiberglass batts and rock wool. Is that true? is it worth the added cost?
to add to my question, I see on the video that the roxul is flushed against the bottom of the joist, which is the same thing roxul said when I called. but the guy that I talked to about installation insists tit must be against the subfloor. If I decide on roxul for a crawl space, how should it be installed? thanks!
You have to compare the NRC (Noise Reduction Coefficient) between the fiberglass and rock wool. Plain old fiberglass may not be as good as rock wool in that sense. I would take the Roxul guys advice and install flush to subfloor, the joists may even be tall enough for a second layer of batts.
Hi, I live in a one-story house with wood floors, 8-10 ft ceilings, and a 6’x6’x15’high skylight. Sound travels around so well, you can hear the family room TV in the bedrooms as if you are sitting in front of the TV. The sound travels a full 180 degrees around two corners. You can also carry on conversations between any two points in the house. Sound transmission is incredibly efficient and incredibly annoying, and I’m not sure why. In our two living areas, the ceiling is partially at an angle, from a ceiling height of 8′ up to 10′ in the main section, following the roofline. I think this might be what makes the sound transmission so efficient. I am trying to figure out if I can install some DIY sound absorption panels on the angled part of the ceiling to reduce reflection and increase privacy in our home.
The one other option I did not see talked about was dense packed, or wet (damp) sprayed cellulose. At 3.5 lbs packing is would seem to have the density and the form of it ideal to trap and absorb sound. Any idea how that product would perform? Certainly bit messier to installed and does require some equipment, but much cheaper than spray foam. It does manage to greatly reduce airflow, although not a true air seal like closed cell spray foam.
How effective is Green Glue compared with sound proofing insulation (fiberglass, mineral wool, etc.)? I hear television from my neighbor and want to avoid the expense of removing the wall between us to add insulation. If I green glue my side of the wall and add a new layer of sheetrock in front, how effective will that be vs. the insulation products referred to at the top of this page?
It’s hard to say how they would compare performance-wise, every situation is different. How large is the shared wall? How loud is the TV from the other side?
You answered a question previously to a Milan and attached a YouTube video on soundproofing ceilings between floors. That answered my questions regarding ceilings. In that video the presenter said his previous segment was on soundproofing walls in media rooms. I cannot find it on YouTube. Could you send/ post a link to that previous video that this very straightforward presenter did. Thank you
Z
Could it be this one?
https://www.youtube.com/watch?v=YbWXHUKHJIs
Hi, I live in a co-op that was built in the 50s. Our bedroom shares a wall with our neighbors spare room which will soon be a nursery. Anytime they are in that room they might as well be sitting next to us, you can hear everything. I’m a light sleeper and I’m not really ready to share the joys of their first child with them. I’d like to save the sleepless nights for my own first child. Not to mention I don’t want to be the cause of waking their child either. Any recommendations? We can also hear the downstairs neighbors if you have tips for that as well.
Unfortunately, that sounds like a major project. You might need to contact a contractor about that.
I live in a historical building with rather large windows (thin old glass) that open up to the busy city street of downtown LA. It looks amazing, but is completely worthless for blocking any noise out. Buses, screaming people out for a night on the town, everything you can imagine feels like I’m sitting outside instead of inside sleeping. I was thinking about either making curtains out of a heavy soundproof material, or going as far as building an artificial wall filled with insulation that I can place up in my window frame each night. The window shape is pretty recessed, so I have a decent amount of space to prop something up if needed. I don’t care about anything thermal, I just want to remove as much sound as possible without making a permanent installation.
Any recommendations? Could some of these materials be hung as curtains? Would I have better results making a temporary piece that can be placed up made out of wood and a specific insulation?
Thanks!
Building something to fit snuggly into your window frame is actually a good idea. Some people with home music studios have done the same thing in order to keep their sound from leaking out. Curtains would mostly help dampen echo and sound from within the room.
have to sound proof an interior wall thats just been sheet rocked–can i add layer of sound proofing material and add another layer sheet rock —would that work?
It could, give a look at Green Glue.