An open doorway sure looks exquisite (if built as an open-plan space) but leaves many open areas for airborne intruders. Not having a door can become a huge problem as it lets in outside noise, heat, and cold.
Fortunately, you can soundproof an open doorway with some simple, easily DIY-able solutions. You can block noise from a doorway without a door by using acoustic dividers, acoustic curtains, blankets, door plugs, or you can create a makeshift door by using items in your house.
Before soundproofing an open doorway, make sure you are clear about the level of soundproofing you need in the room, do you wish for a temporary or a permanent solution? What’s your budget? How loud is the noise actually?
Principles Of Soundproofing
You must know the four fundamental principles of soundproofing when attempting to soundproof your room without a door. Knowing this will help you get a better idea of what needs to be done and the appropriate products for it.
Your options are somewhat limited when it comes to blocking sound transmission from an open doorway. This is because with open door spaces you are literally dealing with a blank canvas. You need to soundproof the space from scratch, unlike with doors.
For any soundproofing project to be successful, you need four main principles of soundproofing implemented in the right ratio.
- Absorption
- Damping
- Mass
- Decoupling (not relevant to the soundproofing of an open doorway because an open space cannot be decoupled)
The three (relevant) principles are briefly discussed below:
Absorption
Absorption means making a sound wave “lose” or exhaust all its energy. This is called energy dissipation. When a sound wave comes into contact with a surface, for instance, a wall, some part of the wave gets reflected into the room, some of it passes through it, while the rest gets absorbed.
When a sound wave hits an absorptive material almost all of it gets absorbed. It loses all its kinetic energy before it can reach the other end of the absorptive product. You can use open-celled structures for increasing absorption.
The absorption of high-frequency sound waves results in the reduction of echo and resonance in a space. You can use absorptive products to enhance the acoustic clarity in a room because such materials eliminate the number of bouncing waves.
Damping
Damping means reducing the number of vibrations on/through a surface. Sound waves travel in the form of vibrations from one place to the next.
If you prevent the occurrence of vibrations, you can reduce the ability of sound to travel. However, damping cannot be used on its own. You will have to incorporate other soundproofing techniques to attain complete soundproofing.
Mass
Mass is the most important principle of soundproofing any kind of object, be it a wall, a door, or a door-less doorway.
Thin and light objects vibrate at a much higher pace than heavier and thicker objects. It is fairly easy to explain, a light object has less structure to move. Thus, it is easier for a sound wave to move or vibrate a light object.
Mass is used for blocking sound instead of managing acoustics. A mass-rich base is always the best way to start any soundproofing project. When you combine mass-filled products with damping and absorption, only then can you soundproof an open space like a doorway without a door.
Tips To Soundproof Without A Door
As mentioned earlier, you do not have tons of options to soundproof an open space. Let’s explore them one by one:
Soundproof Blankets
Editor’s recommendation: when it comes to soundproof blankets, the Audimute Absorption Sheets are our favorite. Learn more about them here.
Some heavy-moving blankets can be pretty effective at blocking the transmission of sound through your open doorway.
When choosing a blanket to hang on the doorway, pick the heaviest and the thickest one. The thicker and denser your blanket is, the better it can trap sound waves traveling through the air. These blankets can also be layered up; you can easily add or remove one blanket over the other.
Mounting tape, duct tape, c-clamps, or curtain rods can be used for hanging them. These blankets will also insulate the space against heat and cold.
Acoustic Curtains
Editor’s recommendation: the NICETOWN Blackout Curtains are the absolute best in the acoustic curtain space which is why we confidently recommend them to all readers. Learn more about them here on Amazon.
Acoustic curtains or noise-canceling curtains are a cheap yet very effective option for blocking sound from an open doorway.
Just like blankets, the advantage of using curtains is that you can draw them back when they are not needed. These curtains have an extra layer of mass in the form of fabric, vinyl, or fiberwood. This could also be synthetic fabric, wool, or Rockwool. All of these materials have a high STC rating that is perfect for blocking sound waves during their transit.
All you have to do is set up a curtain rail above the doorframe. Use wall plugs, screws, studs, and a drill, to drill and fix the rail. These curtains will dampen the noise coming in from the other side but won’t completely block it unless you use double or triple layers of it.
Their soft surfaces act as a flexible barrier that neither transmits nor reflects the sound waves hitting them. You can also add velvet drapes on the inner side to enhance the appearance and add more mass for better blockage.
Acoustic Room Dividers
Usually found in offices, an acoustic room divider is used to partition open-plan areas to reduce noise clutter. They are excellent at dampening airborne noise and add mass as well as absorption to the mix.
A high-quality room divider can offer all three qualities in a single frame. The core is filled with mass, topped by a layer of the sound dampener, and covered with an absorptive material at the top to capture as many wandering waves as possible.
As the name suggests, this product will also enhance the acoustics of your room with an open doorway. It will absorb unwanted sound waves from the room leaving an echo-free environment.
They are great at mitigating airborne noise but since they are not the same size as the door, they cannot offer 100% soundproofing. The tallest divider you can find would be 6 feet tall.
To counter this, you can use cushions or blankets, or plugs to close the gaps. Alternatively, you can also add acoustic panels and make them larger and wider as needed.
Make A Door Plug
A door plug is a soundproof door that is not attached to the frame of the doorway. It can be removed whenever needed and stored or moved easily.
You can build it with mass-loaded vinyl, acoustic panels, a medium density fiberboard, acoustic caulk, screws and nails, and screwdrivers. Here’s how you do it:
- Measure the doorframe accurately keeping in mind that the plug is going to sit in snugly.
- Cut MDF in the size of the doorframe, fix the pieces to the sides with nails and screws. Use acoustic caulk to seal the open sides of the doorframe.
- Peel and stick a layer of mass-loaded vinyl or any other sound deadening mat on the inside of the frame. Again, seal the edges with acoustic caulk if needed. Fill the corners of the structure with small triangles of MDF.
- You can add more layers to it if you want more sound blockage. Then add acoustic foam over it with the help of glue. Don’t overuse the glue as it may block the cells of the foam.
- Put the handles on the backside of the box and you have a plug door ready.
Make sure you put the soundproofing material such as layers of MLV on the side that is facing the incoming sound. If you’re stopping sounds from getting out of the room, you can place them on the inner side, otherwise, always place them on the outside.
Create A Makeshift Door
If you cannot afford (or bother with) proper soundproofing products, you can always use the items you already have in your house to create a sound barrier.
The simple rule is, the more mass you have between the outside world and you, the better.
You can use old mattresses, pillows, cushions, blankets, and everything soft and thick to absorb incoming sound waves. This solution is not recommended but if you have no other option, this will do the job.
Conclusion
Doorways and doors always need a little more attention than the rest of the house in every soundproofing project. A doorway is harder to soundproof as you do not have anything on which you can build (mass) upon.
The easiest and cheapest way of soundproofing a doorway without a door is to hang acoustic curtains or blankets to cover the open space. You can remove them just as easily. They will also offer some extra thermal insulation along with soundproofing.
There are some great options listed and explained above that you can use to block the transmission of unwanted noise inside your room. You can also use more than two at a time to achieve your desired level of soundproofing.