6 Simple Ways to Soundproof Interior Doors
The importance of realizing what is the difference between interior and exterior doors is huge, especially for soundproofing purposes. The same goes for a solid core door as well as a hollow core door.
Unlike exterior doors that are built of solid wood, interior doors usually have a hollow core.
With that said, it’s easy to conclude that exterior doors are much heavier, more massive, while interior ones are frankly lighter.
This reflects into interior doors soundproofing power. They are a lot easier for the noise to pass through, unlike their exterior counterparts which are much better at blocking sound in general.
Interior doors are usually hollow core doors and that is the reason why they are not technically soundproof doors. Not the best for blocking off normal speech or loud speech for that matter.
And you might not even live in a busy town, yet your doors might be the main source of the noise problems you experience on a daily basis.
In most cases they are the thinnest barrier between you and noises outside the house.
Therefore, they require a bit more soundproofing.
I had interior doors all over my first apartment, and it was highly noisy.
No matter how much privacy they were providing, you could hear anyone without any problems behind those doors like there were no doors at all. Even normal speech sounded like it took place in the same room!
Definitely not the best solution for home offices if you ask me! Especially if you are dealing with loud speech sounds on a daily basis.
So, I have found out about a couple of solutions for my interior door soundproof issue.
Of course, changing doors is somewhat expensive, so soundproofing is a great alternative.
In this article, I will explain the basics of soundproofing interior doors, and hopefully help you solve your problem in the most effective way.
So, let’s get to the point.
6 Steps to Soundproof Interior Doors Effectively
What You'll Be Needing:
Some of these methods are quite usual when it comes to soundproofing doors.
However, interior doors function differently from exterior doors as they are (most commonly) sliding or folding.
Therefore, as the structure is a bit different, the soundproofing process of a hollow door is slightly different as well.
But how do you soundproof a hollow core door? Keep on reading to find out!
1. Put soundproofing blankets
Wait, what? Blankets on the doors?
Yes, you heard me well. I was sarcastic about them as well, but soundproofing blankets (moving blankets) are an effective solution to the noise problems.
Moving blankets or some may call them acoustic blankets are well-known for their sound-absorbing capability.
Yet they’re extremely useful as a noise reducer for the door – and best of all, you can install & remove them easily.
They are extremely thick blankets, designed for the purpose of soundproofing that will absorb any sound on its way to your room.
Hanging these on your sliding doors might solve your problem completely or at least cut the noise in half. This will greatly prevent sounds from coming through the door.
It’s quite logical and natural - the more layers there are, the better the insulation is.
Therefore, adding an extra layer of defense to your doors will reasonably decrease the noise. Most doors don't even have that.
Usually, one layer of moving blankets is enough, but if you are still hearing the noise, feel free to add more.
Moving blankets, or acoustic blankets are quite big, and they belong to an affordable price point category.
You can find some samples for like $30-$40.
It might not be the perfect solution for the noise problem, but in most cases effective. Of course, it all depends on the noise level, the room, the door type, how the door opens, existing air gaps, house size, etc.
Frankly, I do not prefer their design, but there are some other beautiful blankets as well that you should check out.
Not only that you will benefit from noise insulation, but these blankets can add to your room’s overall appearance.
Nevertheless, you can use them as a great solution to the thermal leak.
2. Use acoustic panels
There is another way to add some soundproofing mass to your sliding interior doors without altering the door frame.
Acoustic panels are frequently used in soundproofing studio purposes.
You need to know that there are two main types of acoustic panels. The first ones are foam panels, and the second fiberglass panels.
Even though both types are known as a great soundproof solution for the doors, foam panels are quite impressive in reducing the echo, while fiberglass panels are highly effective in blocking the noise.
Therefore, I recommend using these fiberglass panels.
Of course, you can use both in order to reduce the echo and block the noise.
However, fiberglass panels cost a bit more but on the other hand, they are much more effective.
Also, fiberglass panels impact the appearance of the room. They are much more beautiful than the foam panels.
You can choose, because they come in different designs and colors, to fit your interior.
But if the money or design is not a problem and yet you are only interested in the best noise reducer for your door you can get – fiberglass it is!
These panels should reduce the noise coming through your sliding doors.
Nonetheless, they are great for low-frequency noise, and vibrating sounds.
Fiberglass panels are shockproof, moisture-proof, and great thermal insulators as well.
Therefore, you will not only benefit from the noise reduction but with several other things as well.
One or two strips on the back of each panel should do the work.
Whether you use command strips or green glue, you will attach those panels successfully.
Now, the difference will show up later on when you decide to remove them. It will be quite easier to do that if you go with strips.
Panels are somewhat cheap, but make sure that you measure the doors before ordering.
Don’t hesitate to buy a bit more- you can always cut the panel and fit it perfectly.
Here is the difference between regular doors and the interior ones.
Hanging strips are not the best solution when it comes to regular doors.
Since they are widely opened and closed more often, there is a risk of hanging strips falling off.
On the other hand, that can’t happen on the sliding doors.
All in all, these panels are used in the music industry, to soundproof studios.
They will surely help you soundproof your interior doors as well.
3. Seal the holes and cover the gaps
Now, you already know that any open spaces can release the sound and cause too much noise.
It’s one of the most overlooked things when soundproofing an interior door.
When regular exterior doors can release a lot of noise, imagine what interior doors can do with even bigger gaps.
Since interior doors are different from the regular ones, they are full of gaps, and you can’t really use some methods that you can use with regular doors.
Do not despair; there are other methods that you can try.
For example, small gaps in the door frame can be gaped with this weatherstripping tape.
Once done, there is a harder part. You will need to soundproof that space between the doors and the floor.
As we mentioned, some methods can’t be applied as these doors need to slide.
However, if the gap between the floor and the doors is a bigger one (larger than it should be), then you can use an adjustable door sweep.
Basically, I’m not a fan of door sweeps when it comes to interior doors.
However, if you decide to go with this one, you should probably aim for the most versatile one. It's my top choice for door sweeps.
It is self-adhesive, and you will easily do it yourself.
Pros of having a door sweep on interior doors:
- Thermal leak reduced
- Bugs and insects prevented from infesting your room
- Noise reduction
Cons of having a door sweep on interior doors:
- It might make the sliding quite difficult
4. Hang some soundproofing curtains
Curtains on the doors? Well, why not? If it can solve your noise problem, I don’t see the problem.
They are quite beautiful with different designs and colors.
Even though you can just go ahead and purchase noise cancelling doors – do you really need to?
Especially when there are ways to cut down the noise and reduce the sound coming from the outside.
However, soundproofing curtains are great noise fighting products. They do require a bit more effort, but in the end, it’s all worth.
With the thickness that they offer, the noise will be reduced drastically.
They are often used for soundproofing windows, but you can use it for these purposes as well.
The first thing that you need to do is install a curtain rod. Once installed, you would want to buy eyelet curtains.
They are a lot easier to install. Simply hang it on the rod through those eyelets.
In order to reduce the noise make sure that the curtains are big enough to cover the doors completely.
They are extremely effective in reducing airborne noise.
Of course, it all depends on the level of the noise.
Be sure that soundproofing curtains can effectively deal with the medium-to-high sound frequencies.
On the other side, they are not so good against low frequencies.
5. Purchase a barn-door sliding doors
As I already mentioned, the thickness and material of your doors matter a lot.
So, even though sliding doors are commonly made of glass or hollow wooden, you can improvise with the material and purchase some solid wood.
Of course, there is one problem with this solid wood- the price.
Since a door like this goes for around $300, it’s quite a big investment. I mean, it’s big considering other methods.
But as you can see, some of the best door noise cancellation requires a decent up-front investment.
Yet there are affordable ways to soundproof your door in no time.
You can purchase some panel, or use any other method for an at least 10x smaller cash investment.
6. Use a combination of methods
If you are really persistent to deal with this noise problem, then you can simply use various methods at once to soundproof your door.
Combine several of them and you will surely decrease the noise.
For example, use fiberglass panels and soundproof curtains. That will remove the noise by 60-90% on average, if not completely.
As we said earlier- the more layers of defense, the better.
Interior Doors Vs Exterior Doors
A typical interior door is a standard hollow core door. That means it has a hollow core inside.
This is true for all hollow doors.
Hollow core doors leak the most amount of sound waves compared to solid doors. They are much lighter and generally easier to operate or fix.
Some examples of interior doors are wooden, metal or steel doors.
A standard exterior door is usually a solid core door. It is usually heavier with a much bulkier in contrast to an interior steel door. Most exterior doors (solid wood doors) are considered soundproof doors.
STC Ratings For Doors and Walls
Every gap in a wall of a house will always leak sound. All air gaps act in the same way.
This can be quantified using the STC Rating. The STC Rating defines the sound transmission class of a given door.
Higher STC values usually represent solid wood doors, solid core doors, etc.
Lower STC values are true for interior doors with a hollow core.
Here is the breakdown of STC Ratings:
- 20 to 25: most interior hollow-core doors
- 30: solid door, PBC
- 33: standard interior wall with 1/2-inch drywall on both sides and 3-1/2 inches of airspace
- 39: interior wall with 1/2-inch drywall on both sides and 3-1/2 inches of space filled with insulation
- 45: double layer of 1/2-inch drywall on both sides (for a total of four layers of drywall), with 3-1/2 inches of space filled with insulation
- 55 to 60: solid wood slab door
Solid wood doors are best in blocking sound transmission. A high quality solid wood door will also provide an airtight seal.
Used in conjunction with automatic door bottoms and door jambs to create a double seal on either side of a door. Now that's how you soundproof a door!
Install A New Door To Soundproof Your House
Door replacement generally is relatively simple because most stock doors used in almost all homes are of standard dimensions and typically have similar inserts for hinges or locks.
In some instances it is as straightforward as simply disconnecting your old hollow core door from the hinges and replacing it with a new solid door.
Keep in mind that hollow core doors are much lighter than that of a solid wood door.
You might want to reinforce the hinges by using longer more durable screws in the door frame for more stability and control.
How To Choose The Best Soundproof Interior Door?
In order to get the best soundproof results it is advised to choose interior doors that are heavy with the most amount of mass and a solid door frame.
What Is The Cost Of A Soundproof Door?
Soundproof doors can get expensive. They can cost $1,300 to $4,000. That being said, standard solid core doors are relatively cheap and work well for soundproofing a house.
Are Barn Doors Soundproof Doors?
Barn doors have good soundproof capabilities due to their massive weight and size.
Does A Solid Door Reduce Noise?
A solid core door has considerable weight. This is a primary reason why it is good for soundproofing.
Is Door Sweep A Good Soundproofing Solution?
Yes. Door sweeps are effective in sealing air gaps at the bottom of the door reducing sound transmission.
On Soundproofing Interior Doors
In the light of everything aforementioned, soundproofing interior doors is not a rocket science.
True, some methods can be annoying and require a bit more effort, but in the end, peace is priceless, right?
If we put aside a method of buying a solid wood panel for your new interior doors, all of the other methods are quite cheap and affordable.
No more than $50 should be spent (tops).
But if money is no problem, I highly recommend investing in your door noise cancellation equipment since it will be worth every dollar you spent.
Therefore, I hope that this article made your life and your room peaceful.
Soundproofing interior doors is a quick and easy solution if you are looking to keep off those nasty outdoor sounds.
We hope this article was helpful in your soundproof door project!
- Put Soundproofing Blankets
- Use Acoustic Panels
- Seal The Holes And Cover The Gaps
- Hang Some Soundproofing Curtains
- Purchase A Barn-Door Sliding Doors