The Ultimate Guide to the Best Soundproofing Materials
Having a soundproof space draws the line between maddening noise and enjoying quiet repose. This is especially important if you live in a large urban center or next to an airport. Noisy neighbors, construction, heavy traffic, and appliances can also be an infuriating source of unwanted sound.
Instead of allowing your anger to grow and fester, try to treat the problem yourself and look into a solid plan for soundproofing your home, room, vehicle, or even your backyard. Not only will this help to keep arguments at bay, but it will give you some peace of mind.
Whatever your purpose for soundproofing, you’re going to want to do it right. Any improper installation of materials may result in an even worse problem or you may not stop noise at all. Taking the time to decide which method is best for your home or business will be the deciding factor between chaotic noise or serene respite.
- How Sound Moves
- Impact Vs. Airborne Noise
- NRC, SAA; STC
- Noise Reduction Coefficients
- Sound Absorption Average
- Sound Transmission Class or Sound Reduction Index
- Soundproofing vs. Absorption ; Deadening
- Common Mistakes
- Indoor Soundproofing Materials
- Walls ; Ceilings
- Outdoor Soundproofing Materials
- Backyard, Garden or Camping
- Boats, Vehicles ; Automotive
- Swimming Pools
Science; Math Behind Sound
The logistics behind sound is an integral part of understanding how to tackle soundproofing issues. Because sound has the power to penetrate almost anything, even steel, it’s a form of energy complete with calculations and measurements.
When an object vibrates, it creates a push of pressure in the surrounding air. This is the essence of sound. Not that you have to be a stellar mathematician, but there are algebraic and geometric equations in measuring how sound moves.
How Sound Moves
When a particular vibration travels, our eardrums pick up the vibration and sends the signal to our brains as a sound according to the different wavelengths. For instance, bass has long wavelength frequencies and treble has short ones. In terms of soundproofing, it’s going to be far more difficult to block thumping bass from a subwoofer than it will be to drown out talking.
Surface uniformity will also affect how sound travels. The harder, more flat, and parallel surfaces will bounce sound whereas softer and less straight areas will allow for sound to bounce off. This creates two categories of noise pollution: impact and airborne.
Impact Vs. Airborne Noise
An example of impact noise is when sound bounces off or reverberates on a surface during construction. Noise that’s airborne comes from things like conversations, heavy traffic and trains.
Noise, or unwanted sound, travels through steel more than 15 times faster than air. To illustrate, many construction workers talk to each other by thwacking a heavy object against metal beams and walls because of the unmistakable sound it creates.
NRC, SAA; STC
Material Safety Data Specification (MSDA) sheets are a legal document provided by material manufacturers. These contain physical and chemical information relating to safety.
MSDAs for soundproofing materials include ratings to state its effectiveness against sound levels. Most of these lab-produced measurements begin at decibels of human conversation.
There are three different ratings depending on the material and how much sound blockage there is: Noise Reduction Coefficients (NRC), Sound Absorption Averages (SAA) or Sound Transmission Class (STC).
Noise Reduction Coefficients
NRC or Noise Reduction Coefficients are calculations of how much sound absorption occurs after striking any given surface. This is a wonderful gauge for measuring frequencies of human speech, between 250 and 2000 Hz. Music and traffic noise will have a higher frequency threshold.
A “0” says it has perfect reflection while a “1” indicates perfect absorption. Sometimes there will be a rating higher than “1” because of how the laboratory tested the sound.
NRC-rated material tests produce ratings only from the surface. The sides of a soundproof panel, for instance, could very likely absorb more sound depending on the material’s thickness and impermeability.
Sound Absorption Average
SAA or Sound Absorption Average is the average absorption coefficients for octave bands ranging between 200 and 2500 Hz. This supersedes NRC ratings because these go beyond testing specimen material. The higher the SAA value, the better the material absorbs sound.
Like NRC ratings, SAA ratings have a “0” or “1” per square foot of material. This is good for measuring human conversation but not so much for music, equipment noise, traffic or anything below 125 Hz.
Sound Transmission Class or Sound Reduction Index
STC or Sound Transmission Class rates how well a building partition blocks airborne sound; it measures the transmission of sound between spaces of any given assembly’s barrier. This applies to floors, ceilings, walls and windows in the United States. Other countries refer to the Sound Reduction Index (SRI).
The tests use standard frequencies ranging from 125 Hz to 4000 Hz. Graphed transmission-loss values reveal a resulting curve that’s then compared to a standard reference contour. This is what produces an STC rating that can range between 25 and 85 or more. Lower ratings are good for human conversation whereas higher ratings are excellent against most ambient noises like music and traffic.
Soundproofing vs. Absorption ; Deadening
Absorption and deadening are not the same as soundproofing. Where soundproofing actually improves the quality of sound in a room, absorption and deadening only control sound.
If you are looking for complete sound isolation, then you’ll want to incorporate the best of both absorption and soundproofing. It’s going to depend on your situation and what you’re trying to do.
A mistake many people make is not performing the correct calculations to ensure optimal control of sound energy. This can result in purchasing a material that’s too short, rendering any soundproofing efforts ineffective.
Being overly concerned about your budget can also present a problem. If you know something will be better to use than another, but go with it because it’s cheaper, you may not see the results you desire. But if budget is a serious consideration, then there are a few DIY things you can try.
Several Methods to Soundproof ; Control Vibration
Consider each one of the following methods and compare them against your unique situation. You want make sure you’re getting the most effective soundproofing for what you need.
Anything that has good, heavy bulk can work toward soundproofing a room. Furniture like couches, sofas, dressers, wardrobes, desks and bookshelves can all contribute to creating a soundproof environment.
If the sound you’re trying to control accompanies noticeable vibration or reverberation, use a material that will absorb energy. Plastic and rubber are popular for this method of soundproofing because they act like a sponge.
But this isn’t the best or most effective method available. It’s good for attempting to soundproof on a budget or use it in conjunction with other methods.
Converting sound energy into heat through damping is another effective way to soundproof a room. Green Glue and silicon caulk are the best examples against low-frequency noise. These fill the space between two supportive sheet materials, like sturdy wood or drywall. This creates a soundproof panel built-into walls, floors or ceilings.
When sound reaches this special-designed system, it triggers friction in the damping layer, which transmutes the sound into heat energy.
Decoupling is a method best done during initial construction by creating gaps within the structure, interrupting sound travel. You can do it afterwards, but you will have to tear down ceilings, floors and walls or do some other type of dismantling.
Deadening or Dampening
When vibration doesn’t affect excessive sound, then dampening or deadening the sound should suffice. It weakens the energy, preventing the sound from permeating into other rooms. Lead and concrete are the usual go-to for applying this method, but lead can present some health issues.
If this isn’t done right, the noise can actually make matters worse, resulting in a “room-within-a-room” effect. Don’t confuse this method with “damping,” as discussed above.
The blocking method does what the word indicates, it blocks out sound. Anything heavy, thick, bulky and impenetrable will achieve a blockage of sound. This includes things like wood panels, furniture and even ear plugs. Sometimes blocking can also mean bouncing sound back to its source.
Materials Used in Various Situations
There are many materials and products out there that can help reduce noise. But whether you need the soundproofing indoors or outdoors is going to determine which kind you use. One of the worst things you can do is use materials intended for indoor soundproofing and think it’s going to work for outdoors.
Be sure to research each of these suggestions to ensure you’re getting the right kind of material for the job. Also, know you will spend a little money if you’re looking for complete and total sound isolation.
Indoor Soundproofing Materials
The cost of soundproofing a room has many contributing variables like material, room size and the target surface. To do a whole room can range between $360 and $4000, averaging around $1700. An entire home or building can be as little as $1 to $30 per square foot.
Some materials are good for almost anywhere you want to place soundproofing. Foam is one such substance that can affix to any surface with glue, staples, nails or pins. You can cut it to fit a specific size or shape.
Mass-Loaded Vinyl (MLV) is another all-over material that’s good for walls, ceilings, floors, windows and doors. You could literally cover an entire room with the stuff. Most people prefer using MLV because it protects from almost all annoying noises and is a better alternative for lead sheeting. MLV is high-grade vinyl infused with silica or barium salts.
Walls ; Ceilings
- Acoustic Foam Panels or Tile reduces reverberation, noise and echoes for small to medium rooms. They’re affordable, easy to use and quick to install. If you want something with surefire quieting ability, research other materials. These are more often a temporary solution than a permanent one.
- Green Glue, as mentioned earlier, helps to dampen sound through walls. It’s a liquid drywall adhesive that improves drywall’s effectiveness by attaching two sheets of material together. Green Glue is easy to use, reduces time and takes hardly any effort. Applying it with a caulk gun allows every part to get even coverage.
- Low Frequency Absorbing Bass Traps are fantastic in stopping bass noise, but they can absorb any low-frequency sound. These are convenient and cost effective with fast installation. They rest in any corner and deliver impressive results with impact noise.
- Resilient Channels are good for low frequency sound waves, impacting sound by vibrating through the channels rather than walls, cutting off sound from a room.
- The channels are rails of sheet metal boosting the sound insulation properties of sheetrock, plasterboard, drywall and ceilings. It separates from the building’s structure, forcing the sound to travel through the channels before entering a wall or ceiling.
- Rockwool Rockboard, or Mineral Wool, is a fire-resistant and rigid acoustic insulation that can double as thermal insulation. It has a high rate of noise cancellation and perfect for any solid building or structure. This is easy to use and you can cut it into shapes if needed.
- Roxul Acoustic Fire Batts comprise a flexible, premium wool which makes it perfect for flat, supportive surfaces. It’s fire retardant, safe and repels water.
- Soundproof Drywall combines many layers of sheetrock, like gypsum and other layers of steel or ceramics. This is an expensive alternative but a potent and worthwhile investment. This kind of drywall uses density and mass to block the transmission of sound.
- Soundproof Paint is an amazing product, but it’s not a miracle cure-all. You’ll need to apply several layers to form a thick coat that would block sound. So, this one can be very time consuming. You’ll have to roll or spray it on and wait for it to dry before applying another layer.
Sometimes windows shake and rattle from music, trains and construction that can cause frustrating disruptions. There are a lot of options you can go with to get some peace of mind. The price to soundproof windows can range as low as $300 to as high as $2000 per window.
- Soundproof Curtains or Drapes are a dense and thick material used on windows, doors and walls. These contain a triple weave of material in three layers and then joined together. The middle sheet blocks or absorbs the sound. These are cheap and they can double as blackout shade.
- Soundproof Blankets or Acoustic Quilts have a similar construction to the curtains. But they are even thicker, denser, heavier and more solid. Get ones with grommets to hang them.
- Soundproof Blinds cover windows to protect the inside from noise outside. Many varieties and selections are available that include shutters, honeycombs and insulating blinds. Not only do these cancel noise up to 50%, they can also keep heat in winter and keep it cool in summer.
- Soundproofing Window Kits are great if you have the time and motivation to do it. These come with some sort of self-adhesive edging tape and framing trim. You could also magnetically attach a piece of acoustic-designed fiberglass. Or, fit it into a metal frame and drill the frame into the window from the interior.
- Soundproof Glass is perfect for homes and commercial buildings. It captures sound wave energy, making noise next to nothing. This kind of glass blocks up to 95% of most sound.
Sometimes, even if you have a complete soundproof installation, you may notice there’s still a few leaks. This could be due to small cracks, gaps and spaces coming from somewhere around the door. Soundproofing a door can cost anywhere from $40 to $1200.
- Weather Strips are inexpensive self-adhesive rubber foam and available almost anywhere. These are great because they’re quick, easy and you can put them anywhere around the door where a gap exists. Weathers strips can ameliorate window gap problems too.
- Gaskets seal gaps around the door that can not only prevent sound from but also block air from leaking out.
- Sweeps do the same thing as gaskets but they rest under the bottom part of the door by the floor.
- Solid wood doors make for excellent soundproofing material. The heavier and thicker the wood, the better noise cancellation will be.
- Threshold Replacements are good when you don’t want to use a sweep or there’s a huge gap at the bottom of the door. Measure the threshold area and the gap between the floor and the door. Remove the old threshold then cut, fit, and glue or nail the new one.
- You may want to use some caulk for any extra cracks that make themselves known after initial installation.
- Gap Filler Foam is wonderful for filling uneven cracks, leaks and gaps in spots around the door. Apply into spaces and watch it expand. Cut away excess with a knife or saw and then sand it down. You can paint it to match the surrounding wall.
- Be sure to wear gloves and read all manufacturers instructions and suggestions.
- Wood Panel Reinforcement requires medium-density fiberboard that’s a ½” thick. You’ll have to remove the door from its hinges and the knobs. First, use a liquid adhesive on two fiberboards. Then take the adhesive and apply it between your homemade panel and the door.
- Once the sealant has dried, drill a hole where the knob is from the backside.
- Fill the inside of the door if it’s hollow by cutting off the top of the door and filling it up with insulation, sand or foam. You could even try some Gap Filler Foam if you feel like drilling some holes into the door.
Sometimes, flooring requires some soundproofing because of loud noises from the basement or from living in an upstairs apartment, for example. There are a myriad of options to handle this.
- Carpeting in-and-of itself isn’t necessarily soundproof. But, if you get a thick carpet like shag or indoor-outdoor versions, it can suffice in assisting with soundproofing a floor. You’ll have to do this in combination with any of the methods listed below.
- Anti-Vibration Floor Mats this is an inexpensive way to absorb sound. You put them right on the floor to prevent impact noise from speakers, washing machines, dishwashers or anything else producing vibration with sound. They compose foam rubber and come in square shapes.
- There are also little cup-looking mats for legs and pegs for things like machines, amplifiers and speakers.
- Foam Mat Floor Tiles are not very attractive but they’re most likely the quickest and cheapest way to soundproof of any manufactured material listed here. You can put this over existing flooring and remove them if needed.
- You won’t have to adhere, glue, nail, screw or affix these in any permanent way which makes it ideal for renters.
- These tiles contain lightweight EVA foam and are fantastic at absorbing impact noises. They’re water-resistant and give added protection to the floor. Their non-slip, interlocking design makes them safe and easy to assemble but not the most aesthetic to look at.
- Soundproof Floor Underlayment fills up and cushions the floor underneath regular flooring or carpeting. This prevents impact noise and echoes and is moisture-resistant. This means the surface will be free of mold and mildew as well as pounding sound.
- You will have to remove the entire floor to place it underneath.
- Insulated Laminate Flooring is super thick with its underlayment already attached. This is generally made of EVA rubber about two millimeters thick with UV protection. It has click-lock construction that’s simple and quick to use.
- Because it’s so thick, it can also protect against scratches and won’t sustain sun damage while it blocks impact noise. This is perfect for when high-heeled shoes hoof it across the floor.
Outdoor Soundproofing Materials
The first thing to consider when wanting to soundproof an outdoor area is whether you want to prevent sound from leaving or stop it from coming in. Camping, for instance, will have many limits to your efforts, so you’ll want to find a camping spot that accommodates a more soundproof environment.
The biggest mistake most people make when soundproofing an outdoor area is that they’ll use any material intended for indoor soundproofing. In certain instances you can do this, but you should make sure it will be a viable option before you try it.
Consider that cars and boats will have different soundproofing methods than what you’ll use in a garden or during a camping trip. Understand, any amount of outdoor soundproofing will not be encompassing. There will always be a certain amount of sound, but efforts can help reduce noise to a large degree.
Backyard, Garden or Camping
- Hedgerows, trees and grass are great soundproof barriers. Something tall, bushy and thick will soundproof a garden or be a perfect campsite covering. It muffles traffic noise and helps prevent sounds from leaving your immediate premises.
- Acoustic Barrier Fences are a good choice to prevent sound from leaving your backyard. They have two wooden outside faces with a soundproof inner core and tend to stand higher than normal fences. It’s a little pricey, but worth it if you plan to entertain guests or have music playing while you garden. Because of this, it may be a best to have a professional install it.
- If you already have a fence, it doesn’t make sense to tear it down. You can soundproof an existing fence so long as it’s made of wood or vinyl. Your preexisting fence should have a good thickness that’s at least 6 feet high and without decoration. Plug any holes before binding soundproof material over it.
- A fence made of chain-link will be expensive and more of a bother than you might want to handle. This is because a chain-link fence can’t support heavy materials and it rattles in the wind.
- Whatever material you use to soundproof your fence, make sure it has weatherproofing properties as well. Reinforced Mass-Loaded Vinyl is the same as normal MLV for indoor applications. The difference is that it contains weatherproofing substances.
- You could also use Sound Deadening Mats intended for vehicles. These are very dense with little elasticity and effective against penetrating sound waves with the capacity for enduring weather. They usually have an adhesive on the back, so you can place them almost anywhere.
- Sound-Blocking Panels made of porous expanded polypropylene, polyethylene or fiberglass make great garden and yard buffers against unwanted sound.
- Sound Baffles are noise-absorbing panels made of cotton, foam, fiberglass or acoustic fabric and rest over an existing fence. Ensure they are weatherproof or removable in the case of inclement weather.
Boats, Vehicles ; Automotive
- Sound Deadening Spray is generally some sort of water-based product mixed with water which is then applied to surfaces. It doesn’t take a lot of time, but once you start you can’t stop until it’s finished. You must apply it to the whole vehicle and won’t be able to leave it for a later time.
- Dynamat is a mat that deadens sound and durable soundproofing for vehicles of all kinds. It protects against vibrations and noise as well as being heat resistant and odorless. The only problem is cutting so it fits a space and it can be quite expensive.
- FatMat Self-Adhesive Sound Deadener is three inches of butyl rubber. It’s incredible soundproof ability comes from how dense and insulated the material is. You can cut it to whatever desired size you want and its self-adhesive backing allows for easy placement. It not only blocks, absorbs and deadens noise, but it also acts as thermal insulation. This is a fabulous but pricey catch-all.
- You can buy it in sheets or a roll that covers up to 200 square feet.
Soundproofing a pool will depend on whether it’s indoors or outdoors. Many of the suggestions listed above for indoor soundproofing will be beneficial for indoor pools. So things like Acoustic Foam Panels, Sound Baffles or Soundproof Curtains might work so long as they’re weatherproof. But if your pool is outdoors, then look into using Dynamat, reinforced MLV or Soundproof Panels made of fiberglass.
Where to Buy Soundproofing
You can find many materials on Amazon. Of course, there might be some variations at your local hardware store or home improvement emporium. Places like Lowes, Home Depot, Menards or Ace Hardware either should have these in stock or will be able to find some for you. You could also do a bit of research and locate an independent manufacturer.
If you find a soundproofing specialist in your area, they may be able to offer a package deal that includes installation. This may even help you save more money, especially if you’re unsure about what you’re doing.
It may be a good idea to write down every place you find with a list of all the available materials and their alternatives they offer with an indication of how much they will cost. When you’ve found three to five places, sit down and determine which will be best for your needs and budget.
If you’re a creative and innovative person, you may enjoy making your own prototype and experiment with materials found around the house. If you are on a serious budget but have to do something as soon as possible to block sound, you could attempt a DIY. There are a few things you may have around.
- You could try gluing large pieces cardboard with thick fabrics sandwiched between as a DIY soundproof panel.
- If you like the idea of soundproofing curtains, you could use several layers of regular curtains or old, thick blankets.
- Rugs or tapestries can swap out soundproofing blankets as long as they’re thick enough.
- You could glue old yoga mats to doors, floors, walls or even windows. These are actually make for excellent soundproofing materials.
- Use furniture to your advantage, especially if you have large bookshelves or wardrobes. These absorb and deflect sound better than most materials available on the market.
- You could use old towels, blankets or rugs to fill gaps at the bottom of doors.
- If you’re inclined to sewing, blankets, curtains, gaskets and sweeps are an ideal project.
- Pillow stuffing could also work as a filler for gaps in windows and doors.